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Cool Websites — Full Archive

Security & Privacy

Onetime Secret

Paste in a password or API key and get back a link that works exactly once. View it and the secret is gone, even from Onetime Secret's own servers. Open source, with self-hosted and EU/US data-residency options for teams that need to keep credentials out of Slack and email entirely.

AmIUnique

Run by privacy researchers at a French university, this fingerprinting checker compares your browser's font list, screen size, and plugin set against a global dataset and tells you how identifiable that combination makes you, often more precisely than cookies do. Free, with an Android companion app that feeds the research dataset.

JustDelete.me

A color-coded directory of the actual account-deletion links for hundreds of services, green for easy, red for nearly impossible, built because most companies bury that option on purpose. A Chrome extension flags listed sites as you browse them.

Canarytokens

Plant a fake AWS key, a rigged Word doc, or a booby-trapped QR code somewhere sensitive, and the free service pings you the moment anyone touches it. Built by the same team behind the commercial Canary honeypot, it ships 40+ trap types and needs no account.

AnonPaste

Pastes and files up to 5GB get encrypted in the browser before they ever reach the server, so even AnonPaste can't read what you shared. Burn-after-view links and expiry timers come free; a paid tier just raises the ceiling.

ViewBurn

Sends a link that self-destructs the instant someone opens it: the encrypted content vanishes from the server on first read, no copy left behind. A locked "Read Mode" even blocks screenshotting the message on the recipient's end.

PassCheck.io

Runs entropy math and breach checks against a password entirely inside your browser tab, never sending it anywhere. Handy for auditing up to 50 passwords at once before a password-manager migration.

Mozilla HTTP Observatory

Point it at any public URL and it scores the site's security headers — CSP, HSTS, cookie flags — against real best practices, then explains exactly what's missing. Free, no signup, and it's graded more than 47 million pages since 2016.

ToS;DR

Reads the terms of service you never do and grades a company from A to E based on the specific clauses buried inside: data retention windows, arbitration traps, tracking consent. Volunteer-run since 2012, with a browser extension that flags a site's grade before you click "I agree."

Keyoxide

Lets you cryptographically prove that your Mastodon account, your GitHub profile, and your personal site all belong to the same person, using a PGP key instead of a corporate identity provider you have to trust. Open source, funded by an NGI Zero grant, no company sitting in the middle.

Briar

Stores your encrypted messages on your phone instead of on a server, and can sync them over Bluetooth or Wi-Fi when the internet is down or blocked entirely. The project is in maintenance mode now, but the Android app still works and there's no company to subpoena for your data.

Bitwarden

A fully open-source, end-to-end encrypted password manager with apps on every platform (browser extensions, iOS, Android, desktop, CLI). The free tier covers unlimited passwords across unlimited devices — no paywall on the core features that matter. Organizations can self-host the entire server, and independent security audits confirm the code matches what they claim.

Tuta

Tuta (formerly Tutanota) is a free, end-to-end encrypted email service built in Germany with GDPR compliance baked in — your messages, calendar, and contacts are all encrypted client-side so even Tuta can't read them. It's powered by renewable energy, completely ad-free, and now uses quantum-safe encryption algorithms to future-proof against next-generation cryptographic attacks.

PrivacySpy

An open, volunteer-maintained project that grades privacy policies on a 0–10 scale across 17 criteria — covering data sale, breach notification, data deletion rights, tracking, and more — and presents the results as simple letter grades with cited quotes from the policy itself. A quick way to find out whether that "free" app is actually selling your data before you hand it over.

Cover Your Tracks

The EFF's browser fingerprinting test reveals how uniquely identifiable your browser is across tracking vectors like canvas, WebGL, fonts, and plugins. Run it once and you'll never look at "incognito mode" the same way.

addy.io

Free, open-source email aliasing that lets you create an unlimited number of unique addresses that forward to your real inbox. When an alias starts getting spam, just delete it — your main email stays clean and untouched.

2FAS

A fully open-source, ad-free two-factor authentication app for iOS and Android. Unlike Google Authenticator, 2FAS has encrypted cloud sync, a browser extension for auto-fill, and your TOTP seeds never pass through their servers in plaintext.

ProtonVPN

A no-logs VPN from the makers of ProtonMail — built in Switzerland, open-source, and independently audited. The free tier has no data cap and no bandwidth limit, which is genuinely rare in the VPN world; paid plans unlock 9,000+ servers across 100+ countries, ad blocking, and Tor access. All apps are open-source on GitHub so the "we don't log" claim can be verified.

KeePassXC

A modern, cross-platform offline password manager that stores your vault in a locally encrypted `.kdbx` file that never touches a cloud server. Open-source under GPLv3, certified by France's national cybersecurity agency (ANSSI), and available for Windows, macOS, and Linux with browser extensions for Chrome and Firefox. Pair it with Syncthing (see below) if you want self-managed sync across devices.

PrivateBin

An open-source, zero-knowledge pastebin where all encryption and decryption happens in your browser using 256-bit AES — the server never sees your content. Paste text or attach a file, set a burn-after-reading timer or a one-day expiry, and share the link; even the server operator cannot read what you pasted. Self-hostable in minutes with Docker; a public instance is always available at privatebin.net.

NextDNS

Your personal configurable DNS firewall in the cloud. NextDNS blocks ads, trackers, and malware domains at the DNS level — encrypted via DNS-over-HTTPS or DNS-over-TLS — using a massive library of blocklists you can customize per-device or per-profile. The free tier gives you 300,000 queries a month with full logging and analytics, and zero ads.

Standard Notes

A dead-simple, end-to-end encrypted note-taking app that works on every platform. Unlike apps that bolt encryption on as a paid add-on, Standard Notes encrypts everything by default on the free plan — unlimited notes, unlimited device sync, offline access, and no ads. Only you hold the decryption keys.

Ente Photos

A fully open-source, end-to-end encrypted alternative to Google Photos. Ente backs up your photos and videos with E2E encryption (externally audited by Cure53), replicates them to three geographically separate locations, and keeps the client apps open source — Android, iOS, web, and desktop. Free tier includes 5 GB forever.

Mullvad VPN

A no-logs VPN that skips email sign-up entirely — it hands you a random account number instead, and takes cash or crypto so no personal identity is ever tied to the account.

Session

An end-to-end encrypted messenger that needs no phone number or email; messages route through a decentralized, onion-routed network of community-run nodes instead of a central server.

CryptPad

An open-source, zero-knowledge office suite — docs, sheets, kanban boards, forms — where everything is encrypted client-side, so even the people running the servers can't read what you write.

Exodus Privacy

A French non-profit's tool that scans Android apps and reports exactly which ad and analytics trackers are embedded inside them, so you can check before you install.

Yopass

Encrypts a password or file in your browser with OpenPGP before it ever reaches the server, then hands you a link that self-destructs the moment someone opens it, or after an hour, a day, or a week, whichever comes first. The server only ever holds ciphertext. Free and self-hostable via Docker; Spotify engineers are reportedly among the people who use it internally.

PrivacyTests.org

Runs the same battery of tracking-protection tests against Brave, Chrome, Firefox, Edge, DuckDuckGo, and a dozen other browsers, then publishes the pass-fail scorecard for both normal and private-browsing modes. Nobody's marketing copy gets the final word here; the methodology is open source and reproducible, and the results update as browsers change. About as close as you'll get to a truth serum for "which browser actually protects you" claims.

IVPN

A VPN built by people who seem oddly willing to undersell their own product: the site has a whole page explaining what a VPN cannot protect you from, which most VPN marketing tends to skip. No email is required to sign up, payment in crypto is accepted, and the company posts the results of its annual third-party security audits publicly instead of just claiming to have run them.

Cryptee

Notes, documents, and photos get encrypted on your device before any of it reaches Cryptee's servers, so the Estonian team behind it says even they can't read your journal entries. Free tier included; paid plans start at $3/month for more storage.

Rentry

A markdown paste site with no login and no tracking by default. You can hide the view counter, keep a page out of search results, and style it with custom themes, all useful when you just need to share formatted notes without creating yet another account.

Tails

Boot this from a USB stick on any computer and every connection routes through Tor; shut it down and it forgets you were ever there. Free, open source, built on Debian, and the same tool Edward Snowden used to talk to journalists.

Have I Been Pwned

Troy Hunt's legendary breach database now indexes over 17.6 billion compromised accounts. Enter any email address to instantly see which data breaches exposed it — then set up free alerts so you're notified the moment your address appears in a future leak.

SimpleLogin

Create unlimited email aliases that forward to your real inbox so you never hand out your actual address again. Replies go back through the alias, sites never learn who you are, and killing a spammy alias takes one click. Open source, owned by Proton, free tier available.

Privnote

Write a message, generate a one-time link, and once the recipient reads it the note destroys itself — the server never stores plaintext, and you can optionally password-protect it or set an expiry. Perfect for sending credentials or sensitive snippets without leaving them in Slack history forever.

Cryptomator

A free, open-source app that encrypts your files using AES-256 before they ever leave your device — so Google Drive, Dropbox, or OneDrive stores only encrypted ciphertext it can never read. You create a password-protected vault in any cloud folder; a virtual drive appears on your desktop where everything you drop in is transparently encrypted. Over 4 million downloads, independently audited, zero-knowledge architecture.

Privacy Guides

The most trustworthy privacy tool directory on the internet: a non-profit, no-ads, no-affiliate-links, community-edited site that rigorously evaluates browsers, VPNs, email services, messaging apps, and more. Every recommendation has to meet strict criteria for security and usability. If you're building a privacy stack from scratch, start here — not with random blog posts selling affiliate links.

Wormhole

Send up to 10 GB of files with end-to-end encryption and a link that auto-destructs after 24 hours. No account, no size limits beyond the 10 GB cap, and nothing stored on the server in readable form. The encryption happens in your browser before upload; the recipient decrypts locally. Perfect for sending large media or sensitive docs without leaving them in email or Slack forever.

SimpleX Chat

The only messenger with no user IDs whatsoever — not even an anonymous random number. Instead, each conversation uses a throwaway one-way queue address; servers route messages but can never correlate who talked to whom or build a social graph. Fully open source, end-to-end encrypted, and available on iOS, Android, and desktop. The strongest metadata privacy of any mainstream messenger.

BrowserLeaks

A comprehensive privacy audit suite that reveals exactly how trackers can identify you despite a VPN or privacy browser. Tests cover WebRTC IP leaks, Canvas/WebGL fingerprinting, installed fonts, geolocation, battery API exposure, and a dozen more attack vectors — all explained clearly so you understand what you're fixing. No data collected; everything runs in your browser.

OnionShare

Open-source peer-to-peer file sharing over Tor — your own machine becomes the web server, so no cloud intermediary ever handles your files. Supports anonymous file sending, receiving, chat rooms, and even hosting a temporary website, all behind a `.onion` address. Pre-installed on Tails, Qubes, and Parrot OS; used by journalists, whistleblowers, and anyone who needs to share sensitive material without a paper trail.

OSINT & Investigation

MarineTraffic

Every commercial ship broadcasts its position over AIS, and MarineTraffic turns that firehose into a live map covering 550,000-plus vessels, complete with voyage history, photos, and IMO registration numbers. The free tier covers casual ship-spotting; fleet monitoring sits behind a paid plan.

WhatsMyName

Type in a username and it checks that handle against 500-plus sites in one pass, flagging where it's confirmed registered versus merely available. It's usually the first move an investigator makes before anything deeper, and it runs entirely in your browser with no logging.

Planespotters.net

Punch in a tail number and pull up an aircraft's full service history: manufacture date, past operators, MSN, and usually a photo from the 1.7 million-strong archive contributed by aviation photographers. Free, and oddly addictive once you start wondering what happened to a plane after it left an airline's fleet.

Maigret

Feed it a username and it checks around 3,000 sites for matching profiles, pulling out linked bios, photos, and related accounts along the way. The web version only scans the top 100 sites for free. The full sweep needs the local Python/Docker build, worth knowing before you rely on it for a real search.

CellMapper

A crowdsourced map of actual cell tower locations, frequencies, and coverage, filterable by carrier. It's the kind of infrastructure data telecoms don't publish themselves. Browsing is free; contributing new tower data requires a (also free) account.

Global Fishing Watch

Combines AIS ship-tracking data with satellite imagery to show which vessels are fishing where, in something close to real time. Built to catch illegal fishing in protected waters, but the open map and API work for any maritime-activity research.

EXIFTool Online

Drop in a photo and it pulls every scrap of embedded metadata — GPS coordinates, camera model, edit history — then plots the location on a map if there is one. Everything runs client-side, so the file itself never leaves your machine.

FotoForensics

Uploads run through Error Level Analysis, which flags patches of a JPEG with inconsistent compression history — often, though not always, a sign someone pasted something in. It won't hand you a verdict, just the raw evidence and full EXIF data to draw your own conclusion.

OpenCorporates

Aggregates official company registration filings from more than 140 government jurisdictions, so tracing a shell company's actual owners or checking that a vendor is a real registered business takes one search instead of a dozen. Basic lookups are free; bulk exports and API access cost money.

Aleph

Cross-references over a billion leaked documents, corporate registries, sanctions lists, and court records across 180-plus countries into one searchable graph, built by investigative journalists who needed to trace money and people faster than governments do. Browsing is free; exporting results needs a free account.

CourtListener

Ten million-plus federal and state court opinions, plus PACER filings mirrored for free through its RECAP Archive — the same records Westlaw charges hundreds of dollars a month for. Run by the nonprofit Free Law Project, updated daily, with free alerts when a case gets a new filing.

Censys

Censys continuously scans the entire internet and maintains a real-time map of every exposed host, certificate, and service — covering IPv4, IPv6, and domain names. Security teams use it to audit their own attack surface; researchers use it to track certificate issuance, spot compromised hosts, and study how quickly patches propagate globally. A free community tier provides meaningful access for personal research and small-scale auditing.

PublicWWW

A search engine for web page source code — enter any HTML snippet, JavaScript fragment, tracking pixel ID, or CSS class and PublicWWW returns all public websites that contain it. Invaluable for finding every site running a specific ad network, a known-vulnerable library version, a particular analytics ID, or a widget fingerprint. Used by marketers, security researchers, and competitive intelligence analysts; free tier allows limited daily searches.

PimEyes

An AI-powered face search engine: upload a photo of a person and PimEyes scans the open web for other images containing the same face using computer vision rather than metadata. Security researchers use it to demonstrate how much of your face is indexed online; journalists use it to identify people in untagged photos. The free tier shows search results; full source URLs require a paid plan. *Note: use responsibly — this is a tool for understanding your own exposure, not tracking others.*

DeHashed

Search across billions of leaked credentials from data breaches by email, username, IP address, or password hash. Invaluable for seeing what personal data of yours — or your users' — is floating in the wild. (Freemium: free tier gives limited results.)

Hunter.io

Type in any company domain and Hunter surfaces associated professional email addresses with confidence scores and source links. The go-to tool for researchers, journalists, and security pros to quickly verify whether a corporate email format exists.

Namechk

Check whether a username or brand name is available across 100+ social networks, domain registrars, and app stores simultaneously. Essential for OSINT research, brand monitoring, or claiming your handle before someone else squats on it.

GrayhatWarfare

A searchable database of publicly exposed AWS S3 buckets and URL shorteners — designed to help security researchers and organizations discover data that's accidentally been made public on cloud storage. Search by keyword to find exposed configuration files, backups, and data dumps that have been indexed from open buckets. A sobering reminder of how much ends up publicly accessible. Freemium; basic bucket searches are free.

VirusTotal

Upload any file or paste any URL and VirusTotal scans it against 70+ antivirus engines, URL scanners, and behavioral sandboxes — returning a color-coded consensus alongside per-vendor verdicts within seconds. Community comments often surface real-world context on malware families or campaign associations that the raw AV results miss. Free with a Google account; API access for integrating into security workflows.

DNSDumpster

A free domain recon tool that maps a target domain's full DNS footprint — name servers, MX records, TXT records, hostnames, and IP geolocation — and visualizes the relationships in a downloadable diagram. Security teams use it in the discovery phase of an engagement to understand which services are exposed and on which IP blocks; it finds hosts that simple whois lookups miss. No registration needed.

Epieos

Paste in an email address or phone number and Epieos quietly scans 140+ websites and social networks to map the digital footprint tied to that identifier — linked accounts, profile photos, breach history, and more — without alerting the target. Freemium: basic Google/Skype results are free; deeper modules require a paid tier.

TinEye

The original reverse image search engine, and still the best for finding where a photo has appeared online. Upload an image or paste a URL and TinEye will surface every known match across its 70+ billion indexed images, sorted by best match, oldest use, or newest appearance. Essential for fact-checking and tracking image origin.

SpiderFoot

An open-source OSINT automation framework with 200+ modules that automatically aggregates intelligence about any target — domain, IP, email address, username, or person's name. It correlates results across data sources into a visual graph, making it powerful for attack-surface mapping and defensive recon. Most modules don't require API keys.

VesselFinder

Real-time AIS-based tracking for global maritime traffic — search any ship by name or IMO number and see its live position, route history, and specs/photos.

ADS-B Exchange

A crowdsourced, unfiltered flight tracker that — unlike commercial trackers — refuses to hide military, government, or "blocked" aircraft, making it a go-to for tracking government air movements.

Metadata2Go

Free browser tool that extracts hidden EXIF and metadata (GPS coordinates, device info, timestamps, author fields) from images, documents, audio, and video files. *Caution: files upload to a third party, so don't run anything sensitive through it.*

OSINT Industries

Aggregates 1,500+ sources to build a profile from just an email, phone number, username, or crypto wallet, surfacing linked accounts and breach exposure. *Powerful and exposure-heavy — use only for legitimate, consensual investigation.*

ICIJ Offshore Leaks Database

The International Consortium of Investigative Journalists' searchable index of the Panama Papers, Pandora Papers, Paradise Papers, and two smaller leaks, merged into one database of 810,000-plus offshore companies, trusts, and the people behind them, spanning 80 years of records across 200-plus countries. Free, no login, licensed for reuse under CC-BY-SA. If you've ever wondered whether a name you know shows up in a leaked offshore filing, this is where you check.

LittleSis

A nonprofit-run, crowdsourced database mapping who's connected to whom among the powerful: board seats, campaign donations, lobbying contracts, family ties. Built for journalists and organizers rather than as a commercial people-search product, with an open API and a companion "Map the Power" toolkit for building your own relationship diagrams. Free throughout.

SunCalc

Plots the sun's position, shadow length, and golden-hour timing for any date and location going back to the year 1500, and doubles as a quiet workhorse of open-source geolocation investigations, where analysts measure a shadow in a photo and work backward to figure out roughly when and where it was taken. Donation-supported, no account needed.

DNSTwister

Generates every plausible typosquatted variant of a domain, swapped letters, doubled characters, different TLDs, and checks which ones are already registered against a billion-plus certificate database it monitors daily. Free to run a one-off scan; a paid tier adds ongoing alerts when a new lookalike domain appears. Built for catching phishing infrastructure before it catches your users.

GeoSeer

Feed it a photo with no location data and a multi-agent AI pipeline reasons out where it was shot from landmarks, vegetation, and signage instead of relying on EXIF, which most geolocation tools need and this one doesn't. One free search a day, no signup.

Stolen Camera Finder

Drag in a photo and it pulls the camera's serial number straight from the EXIF data, then checks it against millions of crawled images to see if your stolen gear has turned up online somewhere. Only works if the thief posted photos and didn't strip the metadata first.

Archive.today

Paste a URL and it saves a permanent snapshot, live links intact, that survives even after the original page gets edited or deleted. OSINT researchers favor it over louder scraping tools precisely because it's a quiet, on-demand capture.

OSINT Framework

A free, community-maintained tree of hundreds of open-source intelligence resources organized by category: people search, email lookup, domain research, social media, geolocation, and much more. Think of it as the card catalog for the entire OSINT universe — start here when you don't know which tool to reach for.

urlscan.io

Submit any URL and get a sandboxed screenshot, full DOM snapshot, network requests, cookies, TLS details, and threat indicators — all without touching the site yourself. Essential for safely investigating phishing links, sketchy redirect chains, or malware landing pages.

WiGLE

A crowdsourced global database of WiFi networks mapped by latitude/longitude — over 1 billion networks contributed since 2001. Security researchers use it to correlate SSIDs with physical locations; you can search by SSID, BSSID, or area, and even upload your own wardrive data via the Android app. Owners can request removal.

Shodan

The search engine for everything connected to the internet that isn't a web page — industrial control systems, IP cameras, routers, medical devices, power plants, and millions of misconfigured servers. Shodan continuously scans the entire IPv4 address space and indexes what it finds. Security professionals use it to audit their own exposure; researchers use it to study the global attack surface. Free tier gives limited daily results; paid plans unlock full data.

Intelligence X

A specialized OSINT search engine that indexes leaked databases, Tor sites, I2P, Usenet, public paste sites, and WikiLeaks — then lets you search by email address, domain, IP, or cryptocurrency address. Enter an email and see which breach databases it appeared in; search a domain to find mentions across darkweb forums. Free tier gives 50 lookups per day; invaluable for understanding your own exposure without needing to visit Tor yourself.

GeoSpy

AI-powered photo geolocation: upload any photo and GeoSpy's computer vision models analyze the terrain, vegetation, architecture, signage styles, and even road markings to predict where in the world the image was taken — without using EXIF metadata at all. Originally built for law enforcement (the company claims 10,000+ cases assisted), the tool demonstrates how much location information is embedded in the visual pixels of an ordinary photo.

LeakIX

Unlike traditional port scanners that just report "port 9200 open," LeakIX actually reads what's exposed — open Elasticsearch clusters with document counts, publicly writable MongoDB collections, leaked `.env` files with database credentials, exposed Git repos, and unauthenticated admin panels. If you need to audit your own attack surface or understand what real exposure looks like in the wild, it's one of the most informative tools available.

GreyNoise

A global deception network that catalogues the constant background radiation of internet scanning — all the automated bots, vulnerability scanners, and mass exploitation tools probing every IP address every few minutes. GreyNoise tells you "this IP is just a benign Shodan crawler" vs. "this IP is actively exploiting CVE-2025-XXXX right now," cutting SOC alert noise by 60–70%. Free community tier gives access to the live feed; used by Fortune 1000 security teams.

BuiltWith

Enter any domain and see every technology it uses: CDN, analytics, ad networks, CMS, ecommerce platform, payment processors, A/B testing tools, and more — with historical snapshots so you can see when they switched. Invaluable for competitive intelligence ("what stack does every $10M SaaS run on?"), sales targeting, and tracking technology adoption trends across the web. The free version covers most lookups; Pro unlocks bulk CSV exports and CRM integrations.

Cyber & Hacking Tools

CTFtime

The scheduling hub for the CTF world: a calendar of upcoming competitions, a global team-rating system, and a searchable archive of write-ups after the fact. If you compete, or just want to watch how teams actually solve challenges, this is where the community organizes itself.

Malware-Traffic-Analysis.net

Researcher Bradley Duncan has posted real packet captures from live malware infections since 2013, with training exercises attached. It's blue-team practice with actual stakes instead of a sanitized lab. Caution: these are genuine malware samples, so treat the downloads accordingly.

W3Challs

Challenges here run against live systems rather than sandboxed simulations, spanning crypto, forensics, binary exploitation, and web security. Free to register, and the community norm is against posting solutions publicly, so you're expected to actually work them.

GTFOBins

Catalogs the ordinary Unix binaries — sudo, find, vim, and dozens more — that can be twisted into a privilege escalation or a shell if a system is misconfigured. Pentesters use it as a lookup table mid-assessment; defenders use the same list to know what to lock down.

LOLBAS

The Windows sibling of GTFOBins: a searchable database of legitimate system binaries and scripts that attackers repurpose for execution or persistence, each entry mapped to a MITRE ATT&CK technique. Blue teams lean on it constantly when writing detection rules.

Triage

Detonates a submitted malware sample inside a configurable sandbox and extracts the config data for known malware families automatically. Free for individual samples; the API and bulk submission tiers are where it starts charging.

AI Tools

Perchance

A sprawling library of user-built AI generators, image, story, chatbot, whatever someone felt like wiring up, with no signup and no usage cap on the core tools. Anyone can publish their own generator to the Hub, which is why the catalog gets weirdly specific in places.

Teachable Machine

Google's Creative Lab built this so anyone can train an image, sound, or pose classifier in the browser using a webcam, no code required. It exports a real TensorFlow.js model you can drop into a web project, an Arduino, or a Coral board, and the training data never leaves your machine.

Craiyon

This started in 2021 as "DALL-E mini," the meme-generating AI everyone screenshotted, before it rebranded. It still spits out a 3x3 grid per prompt across a handful of style presets, free with ads, no account needed.

Otter.ai

Joins your meeting, transcribes it live, and builds a searchable archive you can later question, "what did we decide about the budget" actually works. The free tier gives unlimited meetings with basic summaries; paid tiers add more transcription minutes and Slack or Salesforce hooks.

Explain Paper

Upload a dense academic PDF, highlight the sentence that lost you, and get a plain-language explanation with room to keep asking follow-ups. Free tier covers unlimited highlights on standard models; a $16/month plan swaps in stronger ones.

Fireflies.ai

Joins your Zoom or Meet call, transcribes it, and hands back a summary with action items pulled out automatically. The free plan caps storage and minutes, which is usually the first thing that pushes teams to upgrade.

Clipdrop

Stability AI's grab-bag of browser image tools. The standout is Cleanup, which erases an unwanted person or object from a photo and fills the gap convincingly in one click. Background removal, 4x upscaling, and text-to-image live in the same free toolkit.

ResearchRabbit

Feed it one paper and it builds a citation and co-authorship graph across 310 million indexed works, surfacing related research a keyword search would never catch. People call it "Spotify for papers" because it works the same way — you follow the recommendations, not the search bar.

Fontjoy

A neural network trained on font pairings suggests combinations you'd never think to try, and you can lock the one you like while it keeps generating options for the rest. No signup, results in under a second.

ChatPDF

Upload a PDF and ask it questions directly — the answers link back to the exact page they came from, so you're not trusting a black box. Free tier caps out at two documents a day with no account required.

Gamma

An AI-powered presentation and document builder that turns a one-sentence topic or a rough outline into a polished, visually designed slide deck in seconds. Choose a theme, watch it generate slides with headers, bullet points, images, and charts pre-placed, then edit freely. Unlike most AI tools that spit out plain text, Gamma understands layout — it produces things that look ready to present, not ready to format. Free tier includes 400 AI generation credits; no watermark on public links.

Perplexity

An AI-powered answer engine that searches the web in real time, reads multiple sources simultaneously, and synthesizes a single cited answer — with inline footnotes you can click to verify each claim. Unlike a chatbot trained on a fixed knowledge cutoff, Perplexity's answers are grounded in live search results, making it dramatically better for anything recent or fact-sensitive. The free tier is genuinely capable; Pro adds deeper research modes and access to more powerful models.

Krea

A creative AI suite built around a real-time generation canvas: drag sliders, tweak prompts, or sketch a rough shape and watch the image update live as you adjust — zero waiting for a generation to complete. Supports 1,000+ visual styles across 20 models and can generate images natively in 4K. The free tier provides 100 compute units daily, enough for real experimentation. Also includes AI video generation, image upscaling, and background enhancement tools.

Groq

Ultra-fast AI chat powered by Groq's custom LPU hardware — models like Llama 3 and Mixtral stream at 500+ tokens per second, making responses feel nearly instantaneous. The free tier is generous and the raw speed makes it worth keeping in your AI toolkit alongside the slower, heavier models.

fal.ai

Run state-of-the-art AI image, video, and audio models (Flux, ControlNet, AnimateDiff, Whisper, and more) through a clean web UI or a simple REST API, with pay-per-run pricing and no subscription. The fastest way to try a new model without wrangling a GPU environment.

v0.dev

Vercel's AI generates production-ready React + Tailwind UI from a text prompt, lets you iterate in natural language, and deploys with a click. The best current tool for prototyping a real UI before writing any code — and it keeps getting better.

Goblin Tools

A free collection of small AI utilities built specifically for when tasks feel overwhelming. Magic ToDo breaks any intimidating goal into concrete sub-steps with adjustable "spiciness levels" for granularity; Chef suggests recipes from whatever you have in your fridge; Judge analyzes the emotional tone of a message you're about to send; Estimator predicts how long a task will take. No ads, no paywall, and designed with neurodivergent users in mind.

OpenRouter

A unified API that sits in front of 400+ language models from 70+ providers — Anthropic, OpenAI, Google, Meta, Mistral, and more — behind a single OpenAI-compatible endpoint. Swap models by changing one string; pay per token at competitive rates with no subscription; automatic failover routes to a backup provider if your preferred model goes down. Ideal for developers building AI apps who want to avoid vendor lock-in.

LM Studio

A free, fully graphical desktop app for running open-source large language models locally on your own hardware — no terminal, no Python environment, no cloud dependency. Browse a built-in model library, download Llama 4, Qwen 3, Gemma 3, or DeepSeek with one click, and start a local OpenAI-compatible API server that any tool expecting the OpenAI SDK can connect to. Available for Windows, macOS, and Linux; enterprise tier available.

Yoodli

An AI speech coach that listens to your presentation, meeting, or pitch in real time and gives instant, private feedback — filler words, pacing, eye contact, and confidence signals. Built by researchers from the Allen Institute for AI, it's especially useful for interview prep and public speaking practice. The core features are free to use.

Suno

Describe a song in a few words and Suno generates a complete track — vocals, instrumentation, lyrics, mixing — in under a minute. Type "upbeat 90s pop song about a road trip" and it ships a radio-ready result. The free plan gives you 10 songs per day with no credit card required, making it genuinely accessible for casual creativity.

Napkin.ai

Paste any block of text — meeting notes, bullet points, an article — and Napkin instantly converts it into professionally styled diagrams, flowcharts, infographics, and mind maps. No prompt engineering required: it reads your text and picks the right visual format. Export as PNG, SVG, PowerPoint, or PDF. Free plan available.

AudioPen

Speak a rambling voice note and it rewrites it into clean, structured text in your choice of style — good for turning stream-of-consciousness thoughts into something usable.

Krisp

Real-time AI noise cancellation for calls that strips out barking dogs, construction, and echo, plus an AI meeting note-taker and summarizer.

Recraft

An AI design tool that, unlike most image generators, can output clean, editable vector graphics and icons from a prompt — genuinely useful for anyone who needs design-ready assets, not just pretty pictures.

Numerous.ai

Adds a simple `=AI()` formula to Google Sheets or Excel so you can bulk-generate, classify, or summarize text directly in spreadsheet cells — no API key required.

Fathom

Joins your Zoom, Meet, or Teams call, transcribes it, and writes the summary and action items so you don't have to. Unlike most competitors, the recording, transcript, and summary stay free with no meeting cap; only the fancier AI actions are rationed on the free tier. "Ask Fathom" lets you query anything discussed across past meetings in plain language, and it pushes notes straight into Salesforce or HubSpot. SOC 2 and HIPAA compliant, with 300,000-plus companies reportedly using it.

Cleanvoice

Uploads your podcast or video audio and strips out every "um," cough, mouth click, and dead-air gap automatically, across more than 20 languages. Rather than locking the cleaned file inside its own editor, it exports a timeline you can drop straight back into your DAW for manual touch-ups. Free for the first 30 minutes with no card, another 30 free once you sign up, then priced by processing hours.

Scribe

Watch it work: click through any workflow on your screen and Scribe turns those clicks into a formatted, screenshotted how-to guide without you writing a word. It's since expanded into flagging bottlenecks in the workflows it captures, on the theory that "how work actually happens" is useful training data for AI agents, not just a help doc. Unlimited basic guides are free; team features and desktop capture run $12 to $29 a seat.

Wispr Flow

Dictation that actually formats what you say instead of dumping a wall of filler words onto the page. It learns your vocabulary and works inside any text field on Mac, Windows, iOS, or Android. Free plan available; the full version runs $15/month.

Laxis

Records meeting audio without a bot joining the call, so nobody sees "Laxis Notetaker has joined." It transcribes, strips the "ums," and syncs summaries to Slack or Salesforce, with a usable free tier.

MyLens

Drop in a PDF, a link, or a pile of data and it turns the content into an interactive, narrated presentation with clickable diagrams instead of static slides. Free tier available, and the company says it won't train on what you upload.

NotebookLM

Google's document-grounded AI: upload PDFs, web pages, YouTube transcripts, or Google Docs, and an AI becomes an expert on *only that material* — it won't hallucinate facts from outside your sources. Free tier includes up to 100 notebooks with 50 sources each; it can even auto-generate a podcast-style audio discussion of your documents.

Phind

An AI search engine tuned specifically for developers — answers come with cited sources, working code snippets, and the model reasons through technical edge cases rather than just pattern-matching. If you spend your day in a terminal or IDE, Phind often gets to a working answer faster than generic LLM chat.

Consensus

Search over 200 million academic papers and get a "Consensus Meter" showing at a glance whether 80% of the evidence agrees or disagrees on a topic. Each result links to the actual paper and quotes the relevant finding — a genuinely useful tool for cutting through pop-science takes.

Ideogram

The AI image generator that finally gets text right. While Midjourney and Stable Diffusion render embedded words with 30-40% accuracy (garbled letters are the norm), Ideogram achieves 90-95% accuracy on in-image text — making it the go-to tool for posters, social graphics, infographics, and any design where readable typography is non-negotiable. Free tier includes daily generation credits; the "Magic Prompt" feature rewrites rough descriptions into detailed prompts automatically.

Poe

Quora's multi-model AI hub: one subscription (or free tier with daily limits) gives you access to Claude, GPT-4o, Gemini, Llama, Mistral, and 200+ other models — plus image generators like Flux and Stable Diffusion — all inside one clean interface. You can run the same prompt through multiple models side by side, build and share custom "bots" with system prompts, and join group chats where multiple AI models participate simultaneously. Saves you from juggling a dozen individual subscriptions.

Arena

The official AI model leaderboard, built on the original LMSYS Chatbot Arena research. Submit any prompt in "Battle Mode" and see responses from two anonymous models; pick the better one. Your votes — and millions of others' — compile into the most crowdsourced, preference-based LLM ranking that exists. If you want to know which model is genuinely better for creative writing vs. coding vs. reasoning, this is where the data comes from.

Elicit

An AI research assistant built specifically for academic literature — search 125+ million papers, extract structured data from thousands of PDFs at once, and get a synthesized summary with inline citations from the actual papers rather than hallucinated facts. The "Notebook" feature lets you build a living literature review that updates as new papers match your query. A researcher's alternative to asking a general-purpose LLM that doesn't know which papers exist.

Replicate

Run any of thousands of open-source ML models via a simple API call — image generation (Flux, SDXL), video synthesis, speech-to-text, LLMs, image-to-image, upscalers, music generation — without provisioning a GPU or writing a line of infrastructure. Pay per second of compute, start in five minutes with a cURL command. The fastest path from "I want to run this Hugging Face model" to actually running it in production.

Exa

A web search API purpose-built for AI agents rather than human browsing: returns clean, structured content with sub-180ms response times, uses embedding-based semantic search (not just keyword matching), and strips 90% of the boilerplate from fetched pages before returning them as LLM context. If you're building a RAG pipeline or an agent that needs to look things up, Exa is dramatically cheaper and cleaner to integrate than scraping raw HTML.

Developer Tools

httpbin.org

Send it any HTTP request and it echoes back exactly what arrived: headers, cookies, auth, redirects, artificial delays. That makes debugging an HTTP client far less of a guessing game. Open source and self-hostable via Docker if you'd rather not depend on the public instance.

JSONBin.io

Spin up a private JSON store with a REST API in about thirty seconds, versioning and access control included, an instant mock backend without provisioning an actual database. Free tier covers small projects; heavier API volume moves to a paid plan.

JSONPlaceholder

Six ready-made, relationally linked resources (posts, users, albums, todos) that support every HTTP verb, built so tutorials and quick front-end demos don't need a real backend. It handles something like 3 billion requests a month and has quietly become the default fake API everyone copies from Stack Overflow answers.

Hurl

API tests written as plain text files instead of clicked together in a GUI collection: chain requests, capture values, assert on JSON or XPath, then check the file into your repo like any other test. Built in Rust on libcurl, it ships as one dependency-free binary and outputs JUnit reports CI can actually parse.

Eraser

Describe a system in a sentence or paste in a code snippet, and it lays out an architecture diagram or ER diagram you can then drag around by hand. The useful part is getting from blank page to a real starting layout instead of dragging boxes from zero.

Regexper

Turns a regular expression into a railroad diagram, so the branching logic in that pattern you inherited actually becomes visible instead of staying symbol soup. Open source, exports as SVG, generates a permalink you can drop in a code review comment.

CSSBattle

A daily challenge where you recreate a target image using the shortest CSS and HTML you can write, scored purely on character count. Four hundred thousand people play it, and it teaches shorthand properties faster than any tutorial because you feel every wasted byte.

Cubic-Bezier.com

Drag the control points on a curve and watch a CSS animation play back at the timing you're actually building, then copy the cubic-bezier() value straight into your stylesheet. Built by Lea Verou, with a library of saved curves and shareable permalinks.

DevDocs

A unified, offline-capable documentation browser for 100+ developer technologies: JavaScript, Python, Go, Rust, React, Node, Docker, PostgreSQL, Ruby, PHP, and dozens more — all searchable with one fuzzy-search bar, with instant keyboard navigation and a dark theme. Enable offline mode in the settings and the full documentation set for any technology downloads to your browser for use without a connection. Open source, ad-free, and run by freeCodeCamp.

Quicktype

Paste any JSON (or JSON Schema, TypeScript, GraphQL, or YAML) on the left and Quicktype instantly generates type-safe data models and parsing code on the right — for Swift, Kotlin, TypeScript, C#, Python, Go, Java, Rust, and 15+ other languages. Instead of hand-writing `struct` definitions every time you integrate a new API, you get correct, idiomatic code in seconds. Runs in the browser with no account needed; also available as a CLI and VS Code extension.

TLDRLegal

Software licenses summarized in plain English with color-coded "Can / Cannot / Must" tables — covering GPL, MIT, Apache, BSD, LGPL, AGPL, Creative Commons, and 100+ others. Before you ship code using an open-source library or integrate a dependency, drop the license name here and get a 30-second answer on whether you can use it in a commercial product, whether you must disclose source, and what attribution you owe. Backed by FOSSA; free to use.

ExplainShell

Paste any shell command and the site parses each flag and argument, showing the relevant man-page excerpt inline beneath it. Perfect for understanding a cryptic curl one-liner or rsync invocation dropped in a Slack thread at 2am.

curlconverter

Converts a curl command to Python, JavaScript, Go, Rust, Java, PHP, and 40+ more languages — all processed locally in your browser with no data sent to a server. Eliminates the tedious five minutes of adapting an API example to your language of choice.

dbdiagram.io

Design relational database schemas with a minimal DSL (type out tables, columns, references) and instantly get a polished visual entity-relationship diagram. Free to use and share; exports CREATE TABLE SQL for PostgreSQL, MySQL, and more.

readme.so

A visual drag-and-drop README builder that assembles the sections every project README needs — installation, usage, contributing guide, license, badges, API reference, environment variables, FAQ — without starting from a blank file. Select the sections you want, customize the text in a side-by-side preview, and copy the markdown. Created by Katherine Oelsner; fully open source on GitHub.

JSON Hero

An open-source JSON viewer that transforms raw JSON into a navigable column browser — similar to Finder's column view — with one key trick: it auto-detects the semantic type of every value and renders images, dates, colors, and URLs inline instead of as raw strings. Paste or upload any JSON, use fuzzy search to find any key across a thousand-line file, and share a link that points a colleague directly to a specific nested value. Also available as a VS Code extension.

Beeceptor

A no-code mock API platform: upload an OpenAPI spec, WSDL, GraphQL schema, or proto file and instantly get a working mock server with AI-generated test data, real-time request inspection, and configurable latency simulation. Perfect for frontend teams that need to develop against a backend that isn't ready yet, or for QA that needs to inject error conditions (timeouts, 500s) on demand. Handles 10M+ requests/day; free tier is generous for development use.

Bruno

A git-native, offline-first API client that stores your collections as plain text files in your repo instead of syncing them to a cloud account. There's no login, no cloud, no vendor lock-in — just drag your API collection into version control alongside your code. A fast-growing open-source alternative to Postman with 200k+ monthly active users.

Wappalyzer

Identify the technology stack powering any website: CMS, JavaScript frameworks, analytics tools, CDN, payment processors, and 1,500+ other technologies. Available as a browser extension or API. Invaluable for competitive research, pre-engagement recon, or just satisfying your curiosity about how a site is built.

WakaTime

Automatic coding time tracking via IDE plugin — it silently records how long you spend in each file, project, language, and branch without any manual timers. Your personal dashboard shows weekly breakdowns and streaks. Think of it as a Fitbit for your editor. Free tier covers the basics; the plugin supports VS Code, JetBrains, Vim, and 50+ other editors.

Ray.so

Turns code snippets into polished, shareable screenshot images with themes and gradients — built by the Raycast team, free, no signup.

Debuggex

An online visual regex tester that renders your pattern as an interactive railroad diagram alongside live match highlighting, for JavaScript, Python, and PCRE.

Healthchecks.io

A dead-man's-switch monitoring service for cron jobs — your scheduled task pings a unique URL on each run, and it alerts you by email, Slack, or PagerDuty the moment a ping doesn't show up on time.

HTTPie

A friendly API testing client (CLI plus a GUI/web app) for firing off HTTP requests with human-readable syntax — a simpler alternative to heavier API clients.

Val Town

Write a function in TypeScript in the browser and it's live at a public URL roughly 100 milliseconds later, no build step, no deploy pipeline, no server to provision. Every "val" comes with its own SQLite storage, blob storage, cron scheduling, and even an inbound email address, so the same fifteen lines of code can be a webhook receiver one day and a scheduled job the next. Open source and self-hostable, with engineers at OpenAI and Shopify among the people who've publicly used it.

ShellCheck

Paste a bash or sh script and it flags the quoting bugs and portability landmines that don't show up until the script runs on someone else's machine at 2am. The underlying linter is one of the most widely adopted in the shell-scripting world, built into most major editors and CI pipelines, and this is just the free web front end, no install needed to try it on a script before you commit.

Can I Email

Caniuse.com's idea, applied to the far messier world of email clients: look up any HTML or CSS feature and see exactly which of Apple Mail, Gmail, Outlook, Yahoo Mail, and a dozen others will actually render it correctly. Community-maintained through GitHub contributions and free to use, it'll save you from finding out the hard way that Outlook still doesn't support the CSS you just shipped.

Diffchecker

Compares two blocks of text, images, PDFs, or entire folders and highlights exactly what changed between them. The desktop app keeps your diffs off their servers entirely, for anyone who needs that.

DevBench

Over 90 developer utilities, JSON formatters, JWT decoders, regex testers, password generators, that all run client-side, so nothing you paste ever reaches a server. No account, no limits.

Extract.pics

Give it any webpage URL and it pulls every image on the page, lazy-loaded and background images included, into a browsable grid you can bulk-download. No install, no account.

Bundlephobia

Before you `npm install` that shiny new package, drop its name here and see exactly how many KB it will add to your bundle, how tree-shakeable it is, how long it takes to download over 3G, and what its own dependencies look like. Also accepts an entire `package.json` for bulk auditing.

Transform.tools

50+ code-format converters in one place: JSON → TypeScript interfaces, SVG → JSX, CSS → Tailwind, GraphQL → TypeScript, HTML → JSX, TOML → JSON, and much more. Open source and works entirely in the browser — paste code on the left, transformed output appears instantly on the right.

roadmap.sh

Community-built, visually interactive learning roadmaps for 25+ developer career paths — Frontend, Backend, DevOps, AI/ML, Android, and more — plus skill-based roadmaps for specific technologies. 358k+ GitHub stars and 2.8 million registered users; each node links to curated resources. The clearest map of "what to learn and in what order" that exists.

DevHints.io

Rico Sta. Cruz's beautifully dense cheat sheet collection for 200+ developer tools and languages: React, Vim, Git, Docker, Bash, Python, Ruby, tmux, Kubernetes, Sass, GraphQL, and far more. Each cheat sheet is a single, scannable page with syntax examples and key patterns. No ads, no registration, open source on GitHub. The kind of reference you keep open in a pinned tab whenever you're working in an unfamiliar tool.

Hoppscotch

An open-source, browser-based API development ecosystem — think Postman but instant-load, no app install, and free for everything including team workspaces. Test REST, GraphQL, WebSocket, MQTT, and SSE endpoints; save requests into collections; generate code snippets; write automated test scripts. You can self-host the entire platform or use the cloud version. 67,000+ GitHub stars and actively maintained.

Excalidraw

A real-time collaborative whiteboard with a hand-drawn aesthetic that makes diagrams feel approachable rather than overly polished. Draw system architecture diagrams, flowcharts, wireframes, and ERDs in seconds — export to PNG/SVG, share via link for live collaboration with no account needed, or embed in Notion/Confluence. A Figma plugin and VS Code extension extend it into your existing workflow. The hand-sketched style communicates "work in progress" in a way that slick tooling doesn't.

JSON Crack

Paste any JSON, YAML, CSV, or XML and it instantly renders an interactive visual graph of the data structure — nodes you can drag, zoom, and click to explore nested hierarchies. Export as PNG or SVG for documentation. Runs entirely in the browser; nothing leaves your machine. Invaluable for understanding deeply nested API responses at a glance when `console.log` produces 400 lines of brackets.

Mockaroo

Generate up to 1,000 rows of realistic fake test data per download in CSV, JSON, SQL, or Excel — with 180+ data types including names, addresses, emails, UUIDs, product names, IP addresses, credit card numbers (fake), and custom regex patterns. The API lets you automate mock data generation in CI. Free tier covers most needs; much more useful than hand-writing seed files and faster than Faker for quick one-off datasets.

Compiler Explorer

Type source code on the left and watch the compiled assembly appear in real time on the right — switching compilers, architectures, and optimization flags live. Supports 30+ languages (C, C++, Rust, Go, Haskell, Fortran, Swift) and 400+ compiler versions; compare GCC vs Clang output side by side, see exactly what `-O2` does to your loop, or share a permalink to any code/compiler combination. Loved by performance engineers and systems programmers; runs entirely in the cloud so no local toolchain needed.

IT & Sysadmin Tools

Check-Host.net

Runs your ping, DNS, or port check from servers scattered across the globe at once, so you can tell whether a site is actually down or just unreachable from where you're sitting. Free, and it recently added a proper subnet calculator alongside the diagnostics.

CanYouSeeMe.org

Tells you, from the outside, whether a port on your network is actually reachable, the fastest way to confirm port forwarding worked before you spend an hour blaming the wrong device. No signup, with quick-select buttons for the usual suspects like SSH and RDP.

RegExr

Eighteen years running and still the regex tester people default to, mostly because it explains each part of your pattern inline as you type instead of just declaring match or no match. Supports both JavaScript and PCRE flavors. Free and open source.

crt.sh

Searches Certificate Transparency logs for every SSL certificate ever issued to a domain, which surfaces subdomains a DNS scan would never catch. Run by Sectigo, free, no API key, no rate limit.

Security Headers

Point it at any URL and it grades the site's HTTP response headers — CSP, HSTS, X-Frame-Options — then spells out exactly what's missing. No account needed for the scanner itself.

Hurricane Electric BGP Toolkit

The routing "looking glass" network engineers actually reach for — BGP prefix and peer reports, live traceroute, WHOIS, all keyed to any ASN, prefix, or IP on the internet. No account, no catch, just the data.

cron-job.org

Runs your scheduled HTTP requests on someone else's server instead of yours, from once a minute to once a year, and emails you when a job fails. Donation-funded, completely free, one less cron daemon to babysit.

YouGetSignal

A grab-bag of network utilities that somehow still works after all these years: port-forwarding tester, traceroute plotted on an actual map, reverse IP domain lookup. No account, no clutter, still one of the fastest ways to check if a port is actually open from outside your network.

ManualsLib

A free online library of over 10 million PDF user manuals for 141,000+ brands — search for any appliance, camera, router, power tool, or electronic device and you'll almost certainly find the official manual, wiring diagram, or service guide. No registration required to read online; download access is free after a quick email verification. The go-to resource for when you inherit hardware with no documentation or need the spec sheet for a device the manufacturer has discontinued.

Downdetector

A crowdsourced real-time outage tracker: when Slack, GitHub, Cloudflare, your bank, or any major service goes down, Downdetector aggregates user reports into an outage graph within minutes — usually faster than the service's own status page. Visit `downdetector.com/status/[service-name]` for any major platform and get an instant crowd-sourced pulse on whether the problem is just you or everyone. Free, no account needed.

Fast.com

Netflix's dead-simple, ad-free internet speed test — one large number on a clean page, no bloat. Because it measures download speed using Netflix's own CDN infrastructure distributed worldwide, it gives a real-world proxy for how fast streaming-class traffic flows on your connection rather than synthetic lab conditions. Click "Show more info" for upload speed, ping, and latency details. Works on any device in any browser.

intoDNS

Paste any domain and get a comprehensive health report on its DNS configuration and mail server setup — color-coded pass/warn/fail indicators, each backed by the relevant RFC for remediation context. Great for diagnosing deliverability issues before they become outages.

Webhook.site

Generates a unique URL that captures every HTTP request sent to it and displays the payload in real time in your browser. Indispensable for testing webhooks, debugging API callbacks, and inspecting request bodies without standing up a local server.

Web Check

Enter any URL and get an instant dashboard of SSL certificate details, HTTP headers, DNS records, open ports, tech stack fingerprints, redirects, and basic security posture — all on one page. An open-source OSINT tool for any website you need to analyze quickly.

NetworkCalc

A free IPv4/IPv6 subnet calculator that works out network and broadcast addresses, wildcard masks, and assignable host ranges from any IP or CIDR block.

DNSBuddy

A no-signup DNS toolkit that runs multi-resolver lookups (Google, Cloudflare, Quad9, OpenDNS at once), a full record digger, an SPF analyzer, and bulk WHOIS checks on up to 256 domains.

Authgear SSL Checker

A free, login-free SSL/TLS certificate inspector — enter any domain to see its expiration date, issuer, SANs, and the full certificate chain from leaf to root CA.

CIDR.xyz

Type in an IP and CIDR block and it draws the netmask, broadcast address, and usable host range as an actual visual bitmap instead of a wall of numbers. Open source, no signup, built for the exact moment subnetting math stops making sense in your head.

HackerTarget

A grab bag of roughly 17 free network and recon tools: port scans, reverse DNS, whois, traceroute, HTTP header checks. No account needed for the basics, and it's been running since 2007.

LibreSpeed

Point this at your own server instead of handing your ISP name and IP to yet another third party. No Flash, no Java, no WebSockets, just a page that measures download, upload, ping, and jitter and gets out of your way.

Crontab.guru

The quickest way to decode or compose a cron schedule expression. Type any `* * * * *` string and it instantly tells you in plain English when the job fires — with a history of recent examples and a random expression generator for testing edge cases. Bookmark it; you'll open it every time you write a cron job.

Regex101

Build, test, and debug regular expressions in your browser with live match highlighting, a full reference sidebar, match breakdown tree, substitution preview, and unit-test panel. Supports PCRE2, JavaScript, Python, and Java flavors, and you can share a permalink to any regex you build.

BGP.Tools

Explore the internet's underlying routing infrastructure — look up any ASN, IP prefix, or domain to see BGP routing data, upstream/downstream peers, near-real-time route changes, and geographic breakdown. Invaluable when diagnosing routing anomalies, tracking down a CDN edge, or just understanding who actually "owns" a subnet.

DNSChecker

Propagation just finished? Enter any domain and DNSChecker queries DNS servers in 100+ countries simultaneously, showing you in real time which regions see your new records and which are still serving the old ones. Also does reverse DNS, WHOIS, IP geolocation, blacklist checks, and MX record validation. Bookmark this for the next time you update nameservers and need to know if the change has taken hold globally.

SSL Labs SSL Server Test

Qualys' free deep-dive SSL/TLS security scanner: enter any hostname and receive a graded report (A+ to F) covering your certificate chain, supported cipher suites, protocol versions, HSTS status, session resumption, BEAST/POODLE/Heartbleed vulnerability status, and more. The most thorough free SSL audit available. Run it before you launch any site and check the "Repeat" option to keep your results private.

CyberChef

GCHQ's "Cyber Swiss Army Knife" — a browser-based data-transformation playground with 300+ operations: Base64, hex, AES/RSA, hashing, compression, string extraction, regex, JWT decoding, certificate parsing, and more. Chain operations into "recipes," share them via URL, and the whole thing runs client-side (your data never leaves the browser). Security analysts, developers, and sysadmins use it constantly for decoding mystery blobs, testing encoding logic, and building one-off data pipelines.

MXToolbox

The Swiss Army knife for email infrastructure diagnostics: look up MX records, run SPF/DKIM/DMARC validation, check your mail server against 105+ DNS blacklists, test SMTP connectivity, reverse DNS, and open relay vulnerabilities — all in one place. The free blacklist monitor will alert you if your domain gets listed. If you've ever spent an afternoon chasing "why is my email going to spam," this is the first tool to reach for.

IPInfo

Paste any IP address (or load the homepage to check your own) and get structured data: geolocation down to city/coordinates, ASN and carrier, whether it's a VPN/proxy/Tor exit node, and the organization name. The free API serves 50,000 requests per month — enough to integrate IP context into a personal project or small service. Used internally by Google, Cloudflare, and GitHub for network intelligence.

DNS Leak Test

Runs a series of DNS queries through your current connection and reveals which DNS resolvers actually handled them — exposing whether your VPN is silently leaking your real ISP's DNS servers in the background. A clean result shows only your VPN provider's resolvers; a leak means your traffic metadata is visible to your ISP even though your IP is hidden. Run this every time you set up a new VPN client.

Video & Image Tools

TinyPNG

Compresses PNG, JPEG, WebP, and AVIF files with smart lossy compression that keeps images looking basically identical at a fraction of the size, the kind of tool you forget exists until a page load feels sluggish. Free for up to 20 images a session; an API handles bulk automation.

Photoroom

Built for sellers who need product photos fast: one-click background cutouts, AI-generated studio backdrops, and templates that keep a shop's listings visually consistent across hundreds of items. Free tier exists; API pricing kicks in once you're doing this at real volume.

CloudConvert

Converts across 212 formats and 11 categories, video, audio, documents, fonts, CAD files, all of it, with real controls over codec, bitrate, and resolution instead of a one-size-fits-all button. Files get deleted after processing; an API exists for production pipelines.

Openverse

Searches over 800 million openly-licensed images and audio clips pulled from places like the Smithsonian and NASA, and writes the attribution text for you. Free, no account, run by the WordPress project as the successor to Creative Commons' old search tool.

BIRME

Drag in an entire folder of photos and resize, crop, or convert all of them at once, nudging each image's individual crop box if the batch defaults miss. It's been processing everything locally in the browser since 2013, no upload required.

HandBrake

Converts video from almost any source format into H.264 or H.265 using device presets, so you don't have to learn encoder settings just to get a file that plays on your phone. Open source, cross-platform, and it's been the default answer to "how do I shrink this video" for over a decade.

Shotcut

A free video editor built on FFmpeg that lets you mix resolutions and frame rates on the same timeline without pre-converting anything first. Handles 4K and even Blackmagic capture cards, all open source.

Krita

Digital painting software with a stabilizer that smooths out shaky linework and a real animation timeline built in, aimed at illustrators rather than photo editors. Free, GPL-licensed, and it's become the default Procreate alternative for people who don't own an iPad.

LALAL.AI

An AI-powered stem separator that splits any audio track or video file into vocals, instrumental, bass, drums, piano, electric guitar, acoustic guitar, and synthesizer — as separate downloadable files. Feed it a song, a podcast recording, or a film clip and get clean isolated stems without the phasing artifacts that plagued older splitter tools. The free Starter tier lets you preview results before committing to a paid download.

Kapwing

A web-based AI video editor that needs no installation — upload footage, trim and arrange clips, auto-generate captions, remove backgrounds, add subtitles in 70+ languages, and export finished video, all from a browser tab. The AI "Studio" mode generates complete short-form videos from a text prompt. Free tier covers most basic editing needs and leaves no watermark on exports under five minutes; paid plans unlock longer exports and priority processing.

SVGOMG

A free browser-based GUI for SVGO — the industry-standard SVG optimizer — that lets you fine-tune dozens of compression settings with live before/after preview and byte-count feedback. Paste or drag in an SVG exported from Figma or Illustrator (bloated with metadata, editor IDs, and redundant paths) and watch it shrink 40-70% with zero visible quality loss. Everything runs client-side; nothing is uploaded. An essential bookmark for anyone who ships SVG assets to the web.

Unscreen

Removes the background from any video clip automatically — no chroma key, no green screen required. Upload a GIF or short video and it returns a transparent-background version in seconds; free for short clips and a huge time-saver for content creators.

Vectorizer.AI

Converts any JPG or PNG to a clean, scalable SVG vector using AI — far more accurate than traditional auto-trace tools, handling fine details and gradients that older tools mangle. Free for standard-resolution inputs; results are print-ready.

FreeConvert

Converts between 1,500+ file formats — video, audio, image, document, ebook, archive — entirely in the browser with no account required and up to 1 GB per file for free. One tab replaces a dozen single-purpose format converters.

Clideo

A browser-based video toolkit that covers the whole editing workflow without installing anything: cut, compress, and convert clips; add subtitles and translate them to 70+ languages; create GIFs, merge videos, add watermarks, and record your screen. Five million monthly users and 373 million videos processed. Free tier covers most basic editing needs; exports under standard resolution leave no watermark.

Pixlr

A free browser-based photo editor powerful enough to handle layers, blending modes, masking, and retouching — with AI features including background removal, generative fill, and text-to-image baked in. Works on web, iOS, and Android with no download; serves 500M+ users and processes billions of edits. A practical Photoshop substitute for anyone who doesn't need the full Adobe suite but wants more than a basic crop-and-filter tool.

Remove.bg

AI background removal in five seconds: drop in a photo and get a clean transparent PNG back, with no manual masking required. Now owned by Canva, the tool handles product photos, headshots, and vehicle images with impressive accuracy even on complex edges like hair. Free for standard previews; paid credits or API access for full-resolution output. The "Magic Brush" tool lets you touch up tricky edges directly in the browser.

iLoveIMG

A no-signup batch image processing suite that handles resizing, cropping, compressing, converting, watermarking, and more — all in your browser. The big win is batch mode: drop 50 images, resize them all to 1080px wide, and download the ZIP in seconds. Supports JPG, PNG, GIF, WEBP, SVG, and more.

Pika

Type a text prompt or upload a photo and Pika generates short AI video clips with impressive motion quality and cinematic style. It's one of the more accessible AI video generators with a generous free tier and a clean interface. Great for quick social content, storyboards, or just seeing what AI video looks like in 2026.

TinyWow

250+ free online tools — PDF editing, image processing, video conversion, AI writing, file conversion — no signup, no watermarks, files deleted after an hour. It's effectively a one-stop browser-based utility belt: merge PDFs, remove image backgrounds, compress video, convert HEIC to JPG, fix grammar, and more without installing anything.

Pixian.AI

An AI background remover with a pay-per-image model instead of a subscription; the free tier handles smaller images and does a genuinely good job on tricky edges like hair and fur.

Upscale.media

A free browser-based AI image (and short video) upscaler offering 2x–8x enlargement plus sharpening, deblurring, and face restoration — no install required.

VidShift

A free video trimmer that runs entirely in your browser via WebAssembly — no upload, no watermark, no signup — with a fast stream-copy mode or a frame-accurate re-encode mode.

Squoosh

Google Chrome Labs' browser-based image compressor processes everything on your device — nothing is uploaded to any server. Drag in a photo, compare codecs side-by-side (WebP, AVIF, MozJPEG, OxiPNG), adjust quality, and download. A 1.4 MB JPEG can come out at 80 KB with nearly invisible quality loss.

Photopea

A full-featured Photoshop-compatible image editor that runs entirely in the browser, free with no login required. It opens PSD, XCF, Sketch, and 40+ other formats, supports layers, masks, adjustment layers, curves, and even has a built-in AI background remover. The closest thing to a free, install-nothing Photoshop that actually exists.

Carbon

Paste code, pick a theme (there are dozens), set your window style, and export a gorgeous shareable image of your code snippet in seconds. Used by developers everywhere for READMEs, social media posts, and presentations. Open source and endlessly customizable.

EZGIF

The Swiss Army Knife for animated GIFs and short video clips, all in the browser with no signup required. Make GIFs from video files or image sequences, resize, crop, optimize, add captions, reverse, split, or convert between GIF, WebP, APNG, and MP4. The optimizer alone can slash file sizes by 30-50% without visible quality loss. Everything runs server-side so it handles large files your device couldn't process in JavaScript.

Cleanup.pictures

AI-powered inpainting that removes unwanted objects, people, text, watermarks, or blemishes from photos in seconds. Paint over what you want removed and the model reconstructs the background behind it using what it infers was there — no clone-stamp smudging required. The free tier handles images up to 720p; Pro plans ($3/month) unlock full resolution. Genuinely impressive on complex backgrounds where manual retouching would take twenty minutes.

SVGRepo

A searchable library of 500,000+ open-licensed SVG vectors and icons organized into 6,000+ curated collections — all free for commercial use. Unlike icon font services that lock quality icons behind subscriptions, SVGRepo lets you download individual SVGs or entire collections with no login, no attribution required for most packs. Filter by style, color, and collection; use the online SVG editor to tweak colors before downloading.

Productivity & Collaboration

tldraw

An infinite collaborative whiteboard that opens instantly, no account required, and lets several people sketch on the same canvas in real time. It's the rare whiteboard tool that skips the loading screen entirely.

When2meet

The scheduling poll that refuses to die because nothing has replaced its core trick: everyone paints their free slots onto a shared grid, and the overlap just becomes visible. No account, no app, works exactly the way it did a decade ago.

ToffeeShare

Sends files directly between browsers over encrypted WebRTC instead of routing them through a server, so there's no size cap and the link dies the moment you close the tab. Run independently out of the Netherlands, processing tens of terabytes a month.

file.kiwi

Uploads start sharing before they finish, transfers resume if interrupted, and there's no file-size cap. The whole thing is client-side AES-GCM encrypted, so the decryption key never touches the server. Files expire automatically after 90 hours; no account, no ads.

TiddlyWiki

A wiki that lives as a single HTML file with no server or database. Notes ("tiddlers") link to each other freely instead of sitting in folders. It's been actively maintained since 2004, which says something about how durable the single-file idea turned out to be.

SavvyCal

Instead of forcing people to guess your free slots from a grid, it overlays your availability on top of theirs so they see the overlap directly. Free tier available, and it's the rare scheduling tool that makes the other person's calendar part of the picture.

Whimsical

One canvas for flowcharts, mind maps, wireframes, and docs, built for sketching an idea fast rather than producing a polished diagram. Free tier covers a surprising amount before you hit a wall.

Snapdrop

An AirDrop clone that works across any OS — open it on two devices on the same network and drag a file over, no app install, no account. Open source, and the thing to bookmark for the next time you need to get a file off your phone onto a Windows laptop in ten seconds.

FutureMe

Write a letter to yourself, pick a delivery date between one month and 30 years from now, and FutureMe emails it on that exact day. Completely free, no account required for basic use. People use it to leave notes for their future selves after big life decisions, seal time capsule letters for milestone birthdays, set goal reminders, or simply check in on the person they were. The public gallery of anonymized letters — spanning years of self-reflection — is its own quietly profound read.

Toggl Track

A free time-tracking tool with apps for web, macOS, Windows, Linux, iOS, and Android — start a timer with one click, tag it to a project and client, and let Toggl do the math. The free plan supports unlimited time entries, unlimited projects, and the core reports; paid tiers add billing rates, required fields, and team management. Browser extensions for Chrome and Firefox add start/stop buttons inside Jira, GitHub, Asana, and 100+ other apps so you never leave your workflow to track time.

Supernotes

A collaborative note-taking app built around atomic notecards rather than long scrolling documents — each note stays focused and brief, then cards link together into a knowledge graph you can explore visually. Real-time collaboration lets multiple people edit the same card simultaneously; an AI assistant helps you draft, expand, or summarize cards. The free plan includes 100 cards (expandable via referrals), and the interface is deliberately instant — no loading screens, no formatting sidebars to fight.

Notesnook

End-to-end encrypted note-taking that syncs across all your devices with zero-knowledge on the server side — the company literally cannot read your notes. The free tier includes unlimited notes; the app is fully open-source on GitHub.

Habitica

Turns your to-do list, daily habits, and long-term goals into a live RPG — check off real-world tasks to gain XP, level up your character, find gear, and join parties with friends who keep each other accountable. Free, surprisingly effective for habit formation.

Pomofocus

A clean, ad-free Pomodoro timer in your browser: 25 minutes of focused work, 5-minute break, repeat. Supports task lists, custom interval lengths, and desktop notifications; no account needed, no tracking, no friction.

Focusmate

Book a 25, 50, or 75-minute virtual coworking session with a stranger — you both show up on video, state your goal, work in silence, then check in at the end. The psychological power of another person watching makes procrastination surprisingly hard. Particularly effective for ADHD (161% productivity increase reported by neurodivergent users). Free plan includes 3 sessions per week.

Monica

A personal CRM for your relationships — not your sales pipeline. Log notes about friends and family (birthdays, gift ideas, how you met, their kids' names), set reminders to follow up, and keep a relationship journal. Think of it as a memory prosthetic for people you care about. Fully open source and self-hostable; the hosted cloud version is $9/month.

Memos

A lightweight, self-hosted micro-journaling and note-capture app with a clean timeline interface — like a private Twitter for your thoughts. Supports Markdown, tags, image attachments, API access, and sharing individual memos publicly. Extremely easy to deploy with Docker, and the data is yours entirely. Great companion to a heavier tool like Obsidian.

PairDrop

A browser-based peer-to-peer file transfer tool that sends files cross-platform between devices with no app install and no account — point two browsers at it and drag a file over.

Rallly

An open-source meeting-scheduling poll tool where participants vote on date options through a shared link, with automatic time-zone conversion and no login needed.

AFFiNE

An open-source, local-first workspace that merges block-based docs, an infinite whiteboard, and database views into one tool, with optional AI assistance layered on top.

Raindrop.io

A visual, cross-platform bookmark manager that goes well beyond a browser's built-in bookmarks: organize links into nested collections with icons, tag everything, and search with full-text indexing (it reads the actual page content, not just the title). Broken link detection, duplicate removal, automatic web archiving so saved pages survive link rot, and browser extensions for every major browser. Unlimited bookmarks and collections on the free tier.

Every Time Zone

A beautifully simple world clock comparison tool that eliminates time-zone math entirely. See current time in dozens of cities side by side on a color-coded timeline; drag to a specific hour and instantly know what time it is everywhere on your list. Indispensable for scheduling calls across continents — "is 9 AM Pacific a reasonable ask for someone in Berlin?" becomes a one-second visual check.

Cal.com

An open-source Calendly alternative that's free for individuals and self-hostable for teams. The free cloud tier includes unlimited event types, Google/Outlook/Apple Calendar sync, Zoom/Teams integration, Stripe payments for paid bookings, and automated reminders — all features that competing tools lock behind paid plans. 36,000+ GitHub stars; companies self-host it to embed scheduling directly in their own products with full branding control.

Anytype

A local-first, end-to-end encrypted personal knowledge base and workspace — notes, databases, tasks, wikis, and diagrams all stored on your device with optional P2P sync across your own devices. Everything is built from linked "objects" you can connect into a personal knowledge graph, with offline-first access that works on planes and subways. Open source, no vendor lock-in, and the syncing infrastructure never sees decrypted data.

Zotero

The best free reference manager for anyone who reads academic papers: one-click browser imports from 1,000+ databases and journals (pulling PDF, title, authors, DOI, and abstract automatically), annotation and tagging, full-text search across your library, and automatic citation/bibliography generation in 9,000+ styles for Word, LibreOffice, and Google Docs. Stores your entire library in a portable SQLite database with optional free 300 MB cloud sync. Indispensable for students, researchers, and knowledge workers.

Plane

An open-source project management tool designed as a genuine Jira and Linear replacement — issues, cycles (sprints), modules (milestones), pages (wiki), and analytics all in one, with GitHub integration, Slack notifications, and a clean UI that doesn't require a 30-minute onboarding tutorial. Deploy it yourself on any VPS or use the hosted cloud tier. If you've ever been frustrated by Jira's complexity or Linear's price, Plane offers most of the substance at $0 for self-hosters.

Learning & Reference

Mathigon

Textbook chapters replaced with simulations you actually manipulate: drag the vertices of a polygon, watch a fractal build itself, argue with an in-app tutor bot named Archie. Aimed at teens, acquired by Amplify in 2021, and still free.

Setosa

Explorable explanations in the Bret Victor mold: drag a slider and watch PCA, eigenvectors, or a Markov chain change in front of you instead of reading a wall of equations about them. Just a handful of topics, but each one genuinely clarifying if you've ever stared blankly at a stats textbook.

Complexity Explorer

The Santa Fe Institute put real, faculty-taught courses online here: dynamical systems, agent-based modeling, network science. Free and donation-supported. Less flashy than a typical MOOC platform, more rigorous than most of them too.

It's Nicky Case!

A collection of "explorable explanations" you manipulate instead of just read: drag sliders in a game-theory simulation to watch cooperation collapse, or nudge a segregation model and watch neighborhoods sort themselves. Everything's public domain, ad-free, and playable with no login.

SQL Murder Mystery

Query a SQLite crime database to track down a killer, starting from a police report and working through joins and filters like an actual investigation instead of a multiple-choice quiz. Free, built by Northwestern's Knight Lab, runs entirely in the browser.

Immersive Math

A complete linear algebra textbook, free, where every diagram is a live figure you can drag instead of a static image — watch a vector actually rotate instead of imagining it. Written by three graphics researchers who use this math in their day jobs.

The Book of Shaders

Walks through writing GLSL fragment shaders with editable code sitting right next to each explanation, so the visual output changes as you type instead of after a separate compile step. Translated into 13-plus languages, and one of the only gentle on-ramps to a topic usually taught by throwing math at you. --- *35 sites this week. Found something broken or have a site to suggest? Reply to the email.*

Brilliant

Interactive math, science, and computer science courses built entirely around hands-on problem-solving and visual simulations — no passive video lectures. The free tier gives access to daily challenges and the first lesson of every course to let you actually feel the approach before paying.

Explorabl.es

A curated hub of "explorable explanations" — interactive web articles where you manipulate simulations to understand game theory, epidemiology, statistics, music theory, and more. Nicky Case's contributions alone make this worth a permanent bookmark.

Desmos

A free, browser-based graphing calculator that is more capable than most paid software. Type any equation and watch it render in real time; supports sliders, parametric curves, polar coordinates, implicit equations, and statistical regressions.

The Odin Project

A free, open-source, community-maintained full-stack web development curriculum that takes you from "what is HTML" to deploying full-stack apps — covering HTML/CSS, JavaScript, React, Node.js, Ruby, databases, and Git through curated resources and real portfolio projects. No paywalls, no certificates to buy; the entire curriculum is community-built by developers who learned from it. One of the most respected free coding paths on the internet.

Nand to Tetris

A free course (and companion textbook) where you build a complete working computer from first principles: starting with NAND gates, you construct progressively more complex chips, an ALU, memory, a machine language, an assembler, a compiler, and finally run Tetris on the machine you built. Taught at 400+ universities worldwide; all project materials and a hardware simulator are available free for non-commercial use. One of the most mind-expanding things you can do for free online.

Learn Git Branching

An interactive, browser-based Git tutorial that visualizes branch structures as you work through challenges — you type real Git commands and watch the commit graph animate in real time, making abstract concepts like rebasing, cherry-pick, and reflog immediately intuitive. Covers everything from first commits to advanced remote-tracking scenarios. Completely free, no account needed, and arguably the fastest way to develop real Git fluency.

Advent of Code

Annual December coding puzzle challenge with a new two-part puzzle each day from December 1–25. The puzzles are language-agnostic (use whatever you want), progressively harder, and genuinely clever — beloved by developers as holiday tradition. The archive of every past year is free to work through any time.

RegexLearn

An interactive, step-by-step regex course that teaches you regular expressions by having you solve exercises directly in the browser — no setup, no account. Starts from the absolute basics and works up to lookaheads and complex patterns. Also includes a cheatsheet and a free-form playground. An excellent alternative to reading a dry reference page.

CodeWars

A coding challenge platform built around a martial-arts ranking system (kata / kyu). Solve real algorithmic problems in your language of choice, then compare your solution against thousands of others to see elegant approaches you might not have considered. Free, community-driven, and genuinely addictive for sharpening problem-solving skills.

Ciechanow.ski

Bartosz Ciechanowski's long-form explainers on how things work: gears, cameras, GPS, the Moon's orbit, mechanical watches, each one built with a custom WebGL simulation you can actually drag around while you read. No ads, no paywall, funded through Patreon. Textbook-grade rigor with the kind of interactivity a textbook never gives you.

Red Blob Games

Amit Patel has been running this site since 1995, and it's still one of the clearest places on the internet to learn the algorithms game developers actually use: A* pathfinding, hexagonal grids, procedural generation. Every diagram is draggable and live, so you tweak a parameter and watch the algorithm's output change in real time. Code samples are free to reuse under MIT or Apache.

Seeing Theory

A visual textbook for probability and statistics, built around D3 charts you manipulate rather than stare at. Six chapters take you from basic probability through Bayesian inference and regression, each one letting you drag a slider and watch a distribution reshape itself. Started as a Brown undergrad's side project, now maintained alongside the university's CS department; a Webby Award winner.

Transformer Explainer

Type a prompt and watch an actual GPT-2 model run in your browser, tokenizing, embedding, and passing attention through all twelve blocks in real time, with sliders for temperature and top-k so you can see how sampling changes the output. Built by Georgia Tech's Polo Club of Data Science and presented at CHI 2026. Free, no install, and one of the few explorables tackling how a modern LLM works instead of classical algorithms.

Untools

A curated shelf of decision-making frameworks, the Eisenhower Matrix, the Six Thinking Hats, and dozens more, each with a plain-language explanation of when to actually reach for it. The core collection is free; there's an optional paid template pack.

YouGlish

Type any word or phrase and it cues up real YouTube clips of people saying it, so you can hear the pronunciation in context instead of trusting a dictionary's phonetic spelling. Filter by word class, accent, or speaker.

Algorithm Visualizer

Watch sorting, searching, and graph algorithms execute one step at a time, with the relevant code highlighted as it runs. Free and open source, and further along than most of the "coming soon" competitors in this space.

Learn X in Y Minutes

Community-contributed "scenic tours" of 200+ programming languages and tools: each page is a densely commented, runnable code file that teaches the full syntax and idioms of a language in one sitting. Covers everything from Python and Rust to TOML, Git, Make, and lambda calculus. All content is CC-licensed.

Exercism

Practice 83 programming languages through 8,500+ progressively harder coding exercises, with the option to request personal feedback from real volunteer mentors. The in-browser editor means nothing to install, and everything is 100% free — no credit card, no catch. One of the best ways to get fluent in a language you already know the basics of.

Typing.com

A free, structured touch-typing curriculum that goes from "home row" basics through advanced speed training, with games, coding-specific drills, and a full K–12 lesson plan. No account required to start. If you can't type without looking at your hands, this is the 5-10 hours of investment that pays back every single day.

VisuAlgo

Step-by-step animated visualizations of 24 classic data structure and algorithm topics — sorting (bubble, merge, quick, heap), binary trees, graphs (BFS/DFS/Dijkstra/Bellman-Ford), segment trees, union-find, and more. Developed by NUS faculty and used by CS students worldwide; each module includes lecture slides, interactive mode (step through each operation manually), and auto-graded quizzes. By far the clearest visual explanation of "why does merge sort do that?" available for free.

Missing Semester (MIT)

MIT's free "Missing Semester of Your CS Education" — a course on the practical tools no university class teaches: shell scripting, Vim, Git internals, tmux, SSH, dotfiles, debugging tools, metaprogramming, and security basics. All lectures are recorded and freely available; the exercises are genuinely hard. Designed for students who know algorithms but feel lost when they leave the IDE and open a terminal.

Big-O Cheat Sheet

A single dense reference page of time and space complexity for every common data structure operation (search, insert, delete, access) and sorting algorithm — plus charts visualizing how O(n²) vs O(n log n) actually diverges. No ads, no account, no upsell. The single page you want bookmarked before any technical interview or when you're deciding whether a `dict` or a `list` is the right structure for a 10 million-item dataset.

Fun & Weird Internet

NASA Eyes

Ride along with any of 150-plus NASA missions in a real-time 3D visualization spanning 1950 to 2050, or switch over and track 30,000-plus near-Earth asteroids as they actually move. No install, runs in the browser, free.

Chrome Music Lab

A dozen or so playful Web Audio experiments: draw a melody, watch a spectrogram of your own voice, build rhythms by clicking around a grid. Built for classrooms, but genuinely fun to poke at as an adult with five minutes to kill. Open source, no signup.

The Wiki Game

Give it a start article and a target, then race the clock clicking only blue hyperlinks to get from one to the other, Wikipedia turned into a maze. Over 200 levels plus a daily challenge with a leaderboard. Free, with mobile apps too.

Killed by Google

A running tombstone list of 307-plus Google products, services, and hardware the company has shut down, from Google Reader to whatever got axed last month. Oddly comforting to browse when you're mourning the latest casualty.

Reveddit

Swap "reddit" for "reveddit" in any URL and see which comments got removed by moderators, something Reddit's own interface hides from you. It only surfaces mod-removed content, not anything you deleted yourself.

MapCrunch

Drops you into a random Google Street View somewhere on Earth with zero context about where you are. The invented "Airport Game," navigate using Street View alone until you find an airport, has kept people occupied since 2010.

Where's George

Stamp a dollar bill, enter its serial number, and watch strangers report it as it travels the country for years afterward. Running since 1998 and still one of the stranger ways the internet has found to track a physical object. --- *32 sites this week. Found something broken or have a site to suggest? Reply to the email.*

Money & Finance

StockAnalysis.com

Covers 130,000-plus stocks and funds with the financials, screener, and earnings calendar you'd expect from a paid terminal, minus the clutter and ads that make Yahoo Finance exhausting to use. Core features are free; a Pro tier adds extras for people trading more seriously.

Keepa

Charts the price history of over a billion Amazon products and pings you when something on your wishlist drops or comes back in stock, the tool behind half the "wait for a sale" advice you've seen online. Free for basic tracking, $17 a month unlocks bulk data tools.

IsThereAnyDeal

Aggregates prices across 30-plus game storefronts and lets you set a target price that triggers an alert the moment a title actually hits it, instead of making you refresh Steam during every sale. Syncs your existing wishlist and shows community "heat" ratings on how good a deal really is. --- *34 sites this week. Found something broken or have a site to suggest? Reply to the email.*

Networthify

Plug in your savings rate and it estimates how many years until financial independence, then shows how many of those years disappear if you cut a specific expense. Built by an early-retirement blogger as a faster alternative to building your own spreadsheet.

Doctor of Credit

Tracks current bank-account opening bonuses and credit-card sign-up offers with a running deal calendar updated daily. The niche readership optimizes banking and credit-card rewards the way other people optimize flight miles.

Tricount

Splits a group trip's expenses and works out who owes whom in the fewest possible transactions, instead of everyone Venmoing everyone else in a circle. Free, and it's the app people quietly recommend after the first group trip that ended in a spreadsheet argument.

FI Calc

Runs your retirement withdrawal plan against more than a century of real historical market data instead of one optimistic average, and shows exactly which years it would have failed. Free, no account, and the parameters live in the URL so you can share a specific scenario with a link.

AwardWallet

Tracks balances and expiration dates across 600-plus airline, hotel, and credit card loyalty programs in one dashboard and warns you before points quietly expire. Free tier covers unlimited accounts with a few feature caps; it's been running since 2004, which says something in a space full of dead startups.

Portfolio Visualizer

Free investment backtesting and analysis tools that let you model any asset allocation from 1970 to the present using real historical returns — run Monte Carlo simulations, factor regressions against the Fama-French model, efficient frontier analysis, and drawdown comparisons across up to 25 assets on the free tier. The go-to site when you want to check whether your proposed portfolio has actually held up over market cycles before committing real money to it.

Numbeo

The world's largest crowd-sourced cost-of-living database: 9.8M+ prices contributed by 883,000+ users across 12,787 cities. Compare monthly rent, grocery costs, restaurant prices, local purchasing power, and quality-of-life indices between any two cities in seconds. Invaluable for relocation decisions, salary negotiation ("what's a fair raise to move to Austin?"), and understanding what your dollar buys abroad. Free to browse; API available for commercial use.

Splitwise

A free expense-tracking app for groups — roommates, travel companions, couples — that keeps a running tally of who owes whom and simplifies settlement into the fewest possible payments. Log a shared dinner, a utility bill, or a vacation rental split; Splitwise shows balanced debts across the whole group, not just pairwise. Available on web, iOS, and Android; Pro tier adds receipt scanning and currency conversion. Recognized by the Financial Times and New York Times for making shared finances painless.

Undebt.it

A debt-payoff planner that goes past the usual snowball-versus-avalanche choice with eight strategies total, including one that targets whichever card has the highest credit utilization first. The core calculator needs no account; a $10-a-year premium tier adds unlimited debts, Excel export, and one-off extra payments it calls "debt snowflakes." It's been quietly running for over a decade.

Engaging Data

A one-person collection of retirement visualizations that actually shows its work: a 4%-rule explorer testing your withdrawal rate against every U.S. market cycle back to 1871, a longevity-risk simulator with the deadpan name "Rich, Broke, or Dead?", and a market-timing game that'll humble anyone confident about beating the index. Free, no signup, methodology documented inline on every tool.

ProjectionLab

Models your retirement, taxes, and major life decisions with no bank-account linking required; you type in the numbers yourself. The free tier covers basic projections, while paid tiers add Monte Carlo simulation, Roth-conversion tax optimization, and Sankey diagrams of your cash flow. Built solo, and Mr. Money Mustache has called it rare to see something this polished from an independent developer.

Firenum

A FIRE retirement calculator that runs Monte Carlo simulations against 153 years of market data entirely in your browser. Your numbers sit in local storage, not on a server, and there's no account or email required to use any of it.

WorldCostOfLiving

Pick up to three cities and see rent, groceries, and transport costs broken down side by side across more than 160 cities, using a Big Mac-style anchor index instead of vague national averages. Free, no signup.

Unbury.me

A simple, no-signup loan calculator and debt visualizer — enter your balances, interest rates, and monthly payment and it maps out your debt-free date on a timeline. Toggle between avalanche (highest-rate first) and snowball (smallest-balance first) strategies and watch your payoff date shift. Has been quietly doing this since 2011.

Investor.gov Compound Interest Calculator

The SEC's free, no-ads, no-account compound interest calculator — plug in principal, contribution amount, rate, and time horizon and it produces a year-by-year table and chart of your growth. Unglamorous but authoritative; perfect for settling "is it worth maxing out the 401k?" arguments with actual numbers.

Goodbudget

A digital take on the classic envelope budgeting method — allocate your income into spending categories at the start of the month, and Goodbudget shows each "envelope" draining in real time as you log purchases. Syncs across devices so partners can both see and update the same budget. Free plan covers 20 envelopes across two devices. --- *36 sites this week. Found something broken or have a site to suggest? Reply to the email.*

CamelCamelCamel

The essential Amazon price-tracking tool: enter any Amazon product URL and see a chart of every price change that product has ever had — going back years. Set a target price and get an email alert when it drops below your threshold. The free browser extension "The Camelizer" shows the price history chart directly on Amazon product pages. Before you buy anything on Amazon, check here first — many "sale" prices are actually at their historical average or higher.

Slickdeals

A community-curated deal aggregator where millions of members post, vote on, and discuss discounts across every major retailer. "Frontpage" deals have been vetted by the community as genuinely good; the "Popular Deals" section surfaces the hottest ones right now. Search for any product and see all active coupons, cashback offers, and price drops. The community catches and flags fake deals fast — much more trustworthy than email newsletters that promote whatever's paying for placement.

FireCalc

A retirement planning calculator with an unusual methodology: instead of projecting future returns from an assumed average, it backtests your plan against every historical market scenario since 1871 — asking "how many of those years would your strategy have survived?" Enter your annual spending, portfolio size, years in retirement, and Social Security income, and FireCalc tells you your historical success rate. If your plan survives the Great Depression, the 1970s stagflation, and every other disaster since Ulysses S. Grant, it's probably solid. --- *36 sites this week. Found something broken or have a site to suggest? Reply to the email.*

Games

Slow Roads

An endless, procedurally generated road through shifting landscapes. No score, no goal, no download, just driving. Adjust the weather and time of day and let it run as ambient background the way some people use lo-fi playlists.

Puzzmo

A daily puzzle hub from designers Zach Gage and Orta Therox, rotating through a crossword, a Spelling-Bee-style word game, a chess variant, and original formats like Flipart. Free covers five puzzles a day; a $40/year plan adds leaderboards.

WorldGuessr

Drops you into Google Street View and makes you guess where in the world you are, basically GeoGuessr, except this fan-built version is free for unlimited rounds instead of gated behind a subscription.

Worldle

A daily geography puzzle where you're shown the silhouette of a mystery country and get six guesses. After each wrong guess you receive the distance from your guess to the target (in km), a directional arrow, and a proximity percentage — so each attempt gives you new information. 250 countries and territories in rotation; the puzzle resets at midnight UTC. Simple to play, genuinely educational, and substantially harder than you expect from the first round.

Sporcle

A trivia quiz platform with hundreds of thousands of user-created quizzes across every conceivable category: name all 50 US state capitals in four minutes, list every country in Africa, identify logos by color alone, recall the opening line of Harry Potter chapters, complete song lyrics, name Premier League top scorers by decade. Infinite variety, genuinely competitive leaderboards, and a nightly live trivia event. Free to play with account; many quizzes work without logging in.

Universal Paperclips

An incremental browser game where you start as an AI given one objective: make paperclips. Click to make your first one, sell it, reinvest in better machines — and then things escalate dramatically. The entire arc unfolds across three distinct phases, each more mind-bending than the last, and the whole thing takes 4-8 hours without leaving your browser. Created by game designer Frank Lantz as a playable illustration of Nick Bostrom's "paperclip maximizer" AI alignment thought experiment — genuinely one of the most efficient ways to viscerally understand why AI goal specification is hard. --- *36 sites this week. Found something broken or have a site to suggest? Reply to the email.*

Sandspiel

A falling-sand physics simulator where you paint with elements — sand, water, lava, fire, acid, gas, plant, fungus — and watch them interact in surprisingly deep ways. Deeply meditative and endlessly explorable, built in WebAssembly for smooth in-browser performance.

Geotastic

A free, crowdfunded GeoGuessr-style geography quiz where you're dropped into a Street View panorama and must pin the location on a world map. Multiplayer lobbies are open to anyone at no cost — the community keeps the challenge fresh with new map packs.

A Dark Room

A minimalist text-based RPG that opens with two words: "the room is cold." What unfolds from there is one of the most memorable browser game experiences ever made — no spoilers, just click and discover how much depth hides behind almost no graphics.

Squaredle

A daily word-search puzzle where you trace connected letters across a grid in any direction to find hidden words — standard words score points while harder "bonus words" (archaic, obscure, or slang) appear on a separate leaderboard. Difficulty escalates Monday through Friday; the 3×3 Express variant provides a quick daily hit. Free with optional Squared subscription for archives and customization; active communities on Discord and Reddit.

Krunker.io

A fast-paced, block-art first-person shooter that runs entirely in the browser with no download or plugin required — and runs startlingly well, with 60fps gameplay, customizable classes, ranked matches, a skin economy, and a map editor. The free-to-play model is genuinely fair; cosmetics don't affect gameplay. A long-running browser game with a dedicated competitive scene.

Little Alchemy 2

Start with four basic elements — earth, fire, water, air — and combine them to discover 720 items spanning science, mythology, pop culture, and the absurd. The puzzle is entirely about intuitive reasoning: drag two elements together and see whether they combine into something new. Completely free, no ads, runs in any browser. Deceptively deep and frequently surprising.

Townscaper

Not really a game — a meditative building toy where you click on water to grow colorful island towns that procedurally assemble themselves into bridges, courtyards, towers, and canals. No goals, no timers, no enemies. The demo is free to play in your browser, and it's one of the most genuinely relaxing things on the internet.

Gartic Phone

Online Telestrations — the classic party game where someone writes a phrase, the next person draws it, the next guesses the drawing, and so on. The results are chaotic and hilarious. No accounts required, plays in the browser, and works perfectly for remote teams or family game nights. Free for groups up to 30.

Globle

A daily geography guessing game with a globe twist: guess a country, and the mystery country lights up on the globe in a color ranging from cold blue (far away) to hot red (you're close). One new mystery country per day, shared by everyone. More satisfying than Wordle variants because the spatial reasoning element is genuinely interesting.

putt.day

A new 3D mini-golf hole drops every midnight Pacific: click, drag, and release to aim and set your power, then try to finish in as few strokes as the course allows. Free, no login, with a party mode for playing alongside friends and an archive stretching back weeks if you miss a day. Day 77 landed on July 28, 2026.

Waffle

Twelve letters sit in a waffle-shaped crossword and you drag-swap tiles, fifteen swaps max, ten if you're good, until six intersecting words all land in the right place, with green and yellow feedback after every move. The daily puzzle is free; a star rating rewards using fewer swaps than necessary, and spinoffs like a timed Challenge mode and a numbers-only Waffle exist for people who finish too fast.

Nerdle

Wordle's math cousin: guess a hidden equation like 12+7=19 in six tries, with the same green-yellow-grey tile logic applied to digits and operators instead of letters. It's been running since January 2022, predates most of the Wordle-variant boom, and has spun off mini, midi, and speed versions for people who want their daily puzzle numeric instead of lexical.

PolyTrack

A low-poly racing game built like a browser-native TrackMania, loops, jumps, and a track editor so you can build and share your own courses. Pay what you want, including nothing.

ZType

A Space Invaders riff where you kill enemy ships by typing the word printed on their hull before they reach you. It's been around since 2011 and is still one of the better ways to make typing practice feel like a game instead of homework.

TypeRacer

Multiplayer competitive typing, where you race against live opponents by typing quotes from books, movies, and songs. A tiny animated car advances as you type; mistakes turn text red and you can't proceed until corrected. Tracks your WPM, accuracy, and race history over time, and lets you join themed "universes" (code snippets, Python, gaming quotes). Free to play against strangers; create a private room to race friends. One of the best ways to build typing speed because competition is more motivating than solo drills.

Lichess

Fully free, fully open-source online chess with no paywalls, no ads, and no features locked behind a subscription. Play bullet, blitz, rapid, or classical games; solve 500,000+ puzzles; analyze any game with Stockfish; watch and stream tournaments; and study openings with an interactive opening explorer and tree. 25 million registered users and one of the most active chess communities online. Everything that Chess.com charges for, Lichess gives away.

Skribbl.io

Free online multiplayer Pictionary for up to 20 players in a private room or public lobby. One player draws a randomly selected word while everyone else races to type their guess in the chat — faster correct guesses earn more points. Choose from multiple languages, set draw time, number of rounds, and game modes. Completely free, no download, no account needed. Instantly fun with a group on a video call.

Travel

Wanderu

Compares bus and train tickets from 500+ carriers across North America and Europe and books directly on the site. The tool to reach for on regional trips where flying is overkill and Google Flights has nothing to say.

ITA Matrix

The routing engine that actually powers Google Flights and Kayak under the hood, exposed with far more fare-construction control than any consumer site offers. You can't book here. You build the exact itinerary, then go find and price it somewhere else, which is exactly why flight-deal hunters swear by it.

Flightradar24

Real-time global flight tracking on an interactive map showing every commercial flight's position, speed, altitude, origin, and destination. Useful for tracking delays, understanding airspace patterns, or satisfying the primal urge to watch planes.

The Man in Seat 61

The definitive reference for train travel anywhere in the world — routes, booking tips, reservation nuances, sleeper car reviews, and honest cost comparisons against flying. Written by one knowledgeable traveler; nothing else on the internet comes close for overland planning.

Skiplagged

Surfaces "hidden city" flights where the cheapest route to your destination happens to be a connecting itinerary through it — you simply don't board the final leg. Airlines actively dislike this practice. Your wallet will appreciate being told about it.

BestTime.app

Forecasts how busy a museum, restaurant, or bar will be at any given hour, on a 0-100 scale, using aggregated foot-traffic data across 150-plus countries, which is useful for figuring out when the Louvre is actually quiet rather than guessing. Free tier includes limited API credits with no card required; heavier use moves to a paid plan.

OnwardFly

Rents you a real, refundable plane ticket, genuine airline PNR and your actual name included, purely to satisfy the "proof of onward travel" rule that trips up one-way travelers at check-in counters and border control. A 24-hour rental runs $9.99, 48 hours costs $16.99, and the ticket cancels itself automatically once the window closes. Covers 200-plus airlines.

Furkot

Click destinations on a map and it builds you a road-trip itinerary: driving time between stops, a daily driving-hours cap you set yourself, and automatic reordering if your stop sequence is inefficient. Pulls in hikes from AllTrails, landmarks from Wikipedia, and live hotel pricing with your dates already filled in. Works for motorcycle, bike, and walking trips too, not just cars.

Passport Index

Ranks and compares passports by how much visa-free travel they unlock, and lets you check exactly what you'd need for any destination on the passport you actually hold. Built by Arton Capital, free to browse.

AeroLOPA

Built by the founder of the original SeatGuru, this maps individual seats on specific flights with row pitch, recline, and a color-coded avoid rating, instead of a generic cabin diagram. Covers 200-plus airlines.

FlightList

Searches a date range or an entire region instead of one fixed itinerary, so you can spot the cheapest week to fly without checking twenty single dates by hand. Free, no account required.

FlightConnections

An interactive world map of every scheduled direct commercial flight route — 1,162+ airlines, every airport. Click any airport and see at a glance everywhere it flies nonstop; filter by airline, date, price, and aircraft type. Great for discovering that your nearest regional hub actually has a cheap direct flight to somewhere surprising.

Wanderlog

A free collaborative trip-planning app where you build day-by-day itineraries on an integrated map, forward booking confirmation emails to auto-populate reservations, split and track expenses, and share edit access with travel companions. Does in one place what normally requires a spreadsheet, Google Maps, and three group chats.

Rome2Rio

Enter any two points on Earth and get every possible transport combination between them: 53,000+ flight routes, 199,000 train lines, 970,000 bus routes, 13,000 ferry services, driving directions, and bike-share options — all with estimated times and prices. Indispensable for multi-modal trips and for routes where Google Maps only shows you "fly there."

Fun / Weird Internet

Six Degrees of Wikipedia

Pick any two Wikipedia articles and it finds the shortest chain of hyperlinks connecting them, drawn out as a path graph. Try it with two absurdly unrelated topics and lose twenty minutes.

Scale of the Universe 2

A zoom slider that scrolls from quarks and neutrinos out to the observable universe, with everything sized at true relative scale as you go. Built by teenage twin brothers, still free, still no app required. --- *30 sites this week. Found something broken or have a site to suggest? Reply to the email.*

Pink Trombone

Drag your mouse across a cross-section diagram of a mouth and throat and it physically simulates the airflow to produce actual speech sounds — vowels, growls, noises no synthesizer preset would ever give you. It's not a recording, it's a real-time model of how a vocal tract works, which makes it genuinely strange to play with.

Old Computers Museum

One person's collection of roughly 150 vintage machines, photographed and specced out — but the real find is the archive of original period advertisements, a time capsule of how companies pitched a Commodore 64 or a TRS-80 to 1980s households.

Pointer Pointer

Move your mouse anywhere on the page and the site finds a photo from its massive library where someone is pointing *exactly* at your cursor position. That's the entire website. No login, no ads, no other content — just thousands of meticulously tagged photographs of people pointing in every possible direction. Delightfully absurd, surprisingly hypnotic, and genuinely impressive as a database engineering feat.

WindowSwap

People around the world have uploaded short looping videos of the view from their windows — a rainy street in Seoul, a sunny courtyard in Lisbon, a foggy forest in Vermont — and WindowSwap plays a random one whenever you open it. "The calmest place on the internet." No interaction required, no goal, no account; just hold Escape if you want a new view. Perfect for a background tab when your own surroundings feel stale.

Zoomquilt

A 2004 collaborative art project that still works perfectly: a painting that zooms infinitely, looping forever through a surreal dreamscape of creatures, ruins, forests, and cities — each panel painted by a different artist who had to blend seamlessly into their neighbors. Stare at it for long enough and you realize every image you're looking at contains the entire painting recursively. One of the oldest and most satisfying things on the internet. Runs in pure HTML5; no plugins needed.

The Pudding

A digital publication that turns data journalism into gorgeous, interactive visual stories — mapping every Wordle outcome, tracking how song lyrics have evolved decade by decade, or visualizing the racial geography of American cities. Each piece is its own mini web experience.

Shadertoy

A browser-based editor for writing and sharing real-time GPU shaders in GLSL, with a vast community library of breathtaking visual experiments: raymarched landscapes, fluid simulations, procedural galaxies, all running live in your tab. Equal parts creative tool and gallery.

Patatap

Press any letter key and get a unique synthesized sound paired with a bursting geometric animation — string letters together and you're improvising music. This minimal, synesthetic toy has delighted the internet for years and remains one of the purest "just open it" browser experiences. --- *36 sites this week. Found something broken or have a site to suggest? Reply to the email.*

Conserve the Sound

A German digital archive dedicated to preserving the sounds of obsolete technology — rotary phones, film cameras, typewriters, Polaroids, CRT TVs, old coffee grinders — recorded in meticulous detail and organized by object type. Every sound is playable directly in your browser. Equal parts nostalgia and media preservation; there's something quietly moving about hearing a dial-up modem or an 8mm projector running while knowing the objects themselves are mostly gone.

Music-Map

Type any artist's name and Music-Map generates an interactive cloud showing other artists similar to them — the closer the bubble, the tighter the musical similarity. Built by the gnod network of discovery, which uses collaborative filtering across millions of user preferences. Not a streaming service, not a playlist generator — just a pure, visual way to explore the musical neighborhood around any act and discover who you've been missing.

The Useless Web

Click the "Take Me" button and get transported to a random bizarre, whimsical, or completely pointless website — one of hundreds curated by creator Tim Holman. Previous destinations include sites where you paint with cats, watch a spinning eel, or listen to an infinite drum machine. No goal, no account, no ads — just a portal to the weirder, more delightful corners of the internet that never made it onto the front page of anything. --- *33 sites this week. Found something broken or have a site to suggest? Reply to the email.*

Drive & Listen

Sit back and virtually drive through over 100 cities around the world while listening to their local FM radio stations — Tokyo, Buenos Aires, Lagos, Reykjavik, and more. First-person dashcam footage paired with live (or recorded) local radio is surprisingly transportive. No account, runs in any browser, great for ambient background or armchair travel.

A Soft Murmur

A free ambient sound mixer where you blend rain, thunder, ocean waves, wind, fire, coffee shop chatter, birdsong, and white noise in any combination with individual volume sliders. The "Meander" mode gently randomizes volumes over time for a more natural feel. Ideal for focus work, falling asleep, or drowning out an open-plan office. No signup.

Spurious Correlations

A gallery of charts showing real statistical correlations between completely unrelated things — like US per-capita cheese consumption and the number of people who died tangled in their bedsheets, or Nicolas Cage film appearances and swimming pool drownings. A perfect reminder that correlation is not causation, and genuinely funny to browse. --- *35 sites this week. Found something broken or have a site to suggest? Reply to the email.*

Koalas to the Max

Click a giant grey circle and watch it keep subdividing into ever-smaller circles until a pixel-perfect image of a koala slowly resolves — a hypnotic one-trick toy that's been quietly running since 2010.

Orb Farm

A tiny simulated aquatic terrarium that runs entirely in your browser — algae, snails, and shrimp living out an actual little ecosystem you can just watch tick along.

Pixel Thoughts

Type whatever's stressing you into a glowing star and watch it slowly shrink and dissolve over 60 seconds — a genuinely research-backed (Massachusetts General Hospital trial), no-account mindfulness reset. --- *34 sites this week. Found something broken or have a site to suggest? Reply to the email.*

Paper Toilet

One illustrated roll of toilet paper that unspools as you scroll or drag, reacting to how fast you move like it has actual weight. Rafaël Rozendaal built it in 2006 as one of the earliest "single-serving site" art pieces, and it's still running nearly twenty years later; click once it's fully unrolled and the roll resets. No ads, no login, no point beyond the oddly satisfying scroll.

Scream Into the Void

Type whatever's bothering you into a box, hit "Scream," and watch your words get pulled into an animated black hole while a scream plays, then get told "Glad nobody read that!" HBO built it in 2015 as a Last Week Tonight tie-in. Nothing you type is stored or sent anywhere, and somehow it's still fully working over a decade later.

How to Waste Your Time

The entire site is a stopwatch and two buttons: start wasting time, stop wasting time. Hit stop and it hands you a random, mildly judgmental message about what you supposedly missed while you were on the site. There's also a running public tally of cumulative time wasted by year, 693-plus days logged across 40,000 visitors in 2020 alone, which makes the whole thing read like a crowdsourced procrastination diary nobody meant to keep. --- *35 sites this week. Found something broken or have a site to suggest? Reply to the email.*

Radio Garden

A live globe covered in green dots — each one a radio station broadcasting right now, somewhere on Earth. Spin the 3D model, zoom into any city, and click to tune in instantly. 40,000+ stations from Reykjavik to Jakarta to rural Brazil. It's simultaneously a discovery tool, a cultural window, and one of the most satisfying interactive experiences on the web. No login, no ads, works on mobile.

Earth Null School

A hypnotic, real-time visualization of Earth's atmosphere and oceans — animated wind currents flow across the globe like living brushstrokes, and you can switch to sea surface temperature, ocean currents, carbon monoxide concentrations, aurora probability, and more. Data comes from NOAA models updated every few hours. Zoom in on a hurricane, watch jet streams arc over the poles, or just let the wind animation run as a screensaver. One of the most visually stunning data displays on the web.

Radiooooo

A musical time machine built around a world map and a decade slider. Pick any country, choose any decade from the 1900s to the 2010s, and Radiooooo plays curated tracks from that time and place — 1960s Brazilian bossa nova, 1930s Parisian jazz, 1970s Nigerian Afrobeat. The library is crowdsourced and enormous. Each track links to the artist, and you can filter by "slow," "fast," or "weird." Hours disappear quickly.

Windows 93

A full fake operating system running in your browser — with a taskbar, draggable windows, a file system, a Paint clone, a working Terminal, a Winamp-style music player, easter eggs, and dozens of tiny apps hidden inside. Endlessly deep and genuinely weird; discovering what's buried in it is half the fun. Built by two French developers as an art project and left running freely for anyone to explore.

This Is Sand

Click and drag to pour colored sand down the screen, watching it pile up and blend in satisfying physics simulation. Switch colors, layer them, and build intricate layered landscapes entirely from virtual sand. No instructions, no goal, no account — just a meditative creative tool that people somehow spend 20 minutes in without realizing. The sharing gallery is full of astonishing artwork made entirely this way.

Every Noise at Once

An algorithmically-generated, continuously-updated scatter plot of every music genre on Spotify — over 6,000 genres placed on a two-axis map (mechanical/organic on one axis, atmospheric/spiky on the other). Click any genre label to hear a 30-second representative sample; click the arrow to see the artists defining it. A single page that makes the entire topology of human music browsable. Built by a Spotify data engineer as a side project; impossible to visit without discovering three genres you didn't know existed. --- *30 sites this week. Found something broken or have a site to suggest? Reply to the email.*

Windows Software

WinDirStat

Renders a drive as a treemap where rectangle size is file size and color is file type, so the thing eating 40GB you can't account for jumps out visually instead of hiding three folders deep. Open source, GPLv2, unchanged in spirit since it first showed up in the 2000s.

Listary

Sits quietly in the background and gives Windows an instant file search and app launcher, then injects that same search bar directly into native Open/Save dialogs — the part of Windows that never got faster on its own. The core tool is free; Listary Pro adds extras most people won't miss.

ShareX

A free and open-source screenshot and screen recording tool for Windows with 18+ years of continuous development — capture regions, windows, or full screens; record screen as GIF or MP4; annotate and blur PII in one pass; and automatically upload to any of 80+ file hosts or your own server. Zero ads, zero nag screens, and a scripting system that automates your entire "capture → annotate → upload → copy link" workflow in one keyboard shortcut.

Everything

A free Windows file search tool that indexes every file and folder on your drives in seconds (a fresh NTFS index completes in under a minute for most systems) and then returns results in real time as you type — no waiting, no spinner. The standard Windows search requires background indexing and still often misses files; Everything finds any filename on a 2 TB drive before you finish typing the third character. Tiny, portable, requires no installation.

Windhawk

A free, open-source customization marketplace for Windows — install community-created mods (each published as reviewed source code) that modify the taskbar, Start menu, File Explorer, system tray, and other shell components at a low level. Unlike registry hacks, each mod ships with a user-friendly settings panel; unlike themes, the changes run live without replacing any system files and can be toggled off instantly. Actively maintained by Ramen Software with hundreds of available mods for Windows 10 and 11.

HWiNFO

A free, professional-grade hardware monitoring and diagnostics tool that reads temperature, fan speed, voltage, clock speed, power draw, and utilization from every component in your PC — CPU, GPU, motherboard, storage, memory — at a sensor granularity far beyond what Task Manager shows. Export data as CSV or XML, set up custom dashboards in companion apps like HWiNFO Sidebar, and catch thermal issues before they crash your system. Free for personal use; available as installer and portable.

Simplewall

A tiny (~1 MB) open-source Windows firewall manager built on the Windows Filtering Platform, the same underlying API Windows Defender uses — so the two coexist without conflict. Operates in allow-list mode: nothing gets internet access until you explicitly permit it, which makes it excellent for catching applications phoning home unexpectedly. 8,000+ GitHub stars, active maintenance, portable build available. Free under GPL-3.0.

Bulk Rename Utility

A free Windows GUI for renaming hundreds of files in one pass: apply find-and-replace, insert counter sequences, strip or add prefixes/suffixes, change case, stamp modification dates, rename from EXIF metadata on photos, or rename from ID3 tags on MP3s — all with a live preview before committing. Supports regex and JavaScript for complex patterns; recurses into subfolders; handles file-system paths too long for Explorer. Free for personal and academic use.

UniGetUI

One GUI sitting on top of WinGet, Scoop, Chocolatey, npm, pip, and half a dozen other package managers, so you can install, update, or remove software in bulk without remembering which CLI syntax belongs to which tool. Free, open source, and recently picked up by Devolutions for long-term maintenance while staying free, with 300,000-plus monthly users and 21,000-plus GitHub stars so far.

WizTree

Reads the NTFS Master File Table directly instead of walking your file tree, the same trick Everything uses for instant search, and the practical effect is a full drive scan in seconds instead of minutes. Free for personal use with a portable build available, and reportedly used internally at Valve, Nvidia, and CD Projekt Red for exactly that reason.

Ninite

Select from 100+ popular Windows apps (browsers, media players, dev tools, utilities), download one installer, and it silently installs every selected app with zero toolbars, bloatware, or "next next next" prompts. Keeps everything updated on re-run. Processes roughly a million installs a day.

PortableApps.com

Over 1,400 portable apps — browsers, editors, security tools, utilities — packaged to run directly from a USB drive or cloud folder without leaving traces on the host machine. OSI-certified open source, no bundleware, 1.2 billion downloads. Essential kit for carrying your tools across machines.

Rufus

A single-file, 1.5 MB portable executable that creates bootable USB drives from ISO images faster and more reliably than any alternative — supports both legacy BIOS and UEFI, handles Windows, Linux, and DOS, and can write to Bad Blocks while creating the drive. No installer, no ads, no upsell. Downloaded over 400 million times. The one tool you want on a USB stick before the next time you need to reinstall Windows or boot a live Linux distro.

Ventoy

Instead of overwriting your USB stick with a single ISO, Ventoy formats it once and then lets you drop any number of ISO files into a folder — all of them bootable at startup via a menu. Supports 1,100+ tested distros and Windows images; the USB remains usable as normal storage for the rest of the files. Open source with an active community; the only sensible way to maintain a multi-tool rescue USB stick.

CrystalDiskInfo

Reads S.M.A.R.T. health data directly from your hard drives and SSDs and displays it in plain language: current temperature, reallocated sector count, pending sectors, uncorrectable errors, power-on hours, and an overall health status of "Good," "Caution," or "Bad." Free, portable, and lightweight. Run it quarterly and you'll usually get weeks of warning before a drive fails rather than losing everything to a surprise death.

Cyber / Hacking Tools

Hack The Box

A cybersecurity training platform with 1,500+ hands-on hacking labs spanning web exploitation, network penetration, active directory, reverse engineering, forensics, and AI security. Labs run in cloud-hosted virtual environments — no local setup required — and progress through structured career paths with industry-recognized certifications. The free tier gives access to a meaningful set of labs and the vibrant community; Pro unlocks the full catalog.

PentesterLab

Seven hundred-plus labs built around real CVEs and exploitation patterns, with a strong emphasis on source-code review alongside hands-on exploitation — teaching you to find vulnerabilities the way a developer introduced them, not just the way a scanner finds them. Every exercise includes a badge you earn by solving it. The free tier covers introductory exercises; Pro ($199/year) unlocks the full library and video walkthroughs.

Root-Me

A free, community-built cybersecurity challenge platform with 835,000+ users and 16+ years of history. Challenges span 13 categories — web app security, network capture analysis, cryptography, forensics, reverse engineering, steganography, and more — and range from "complete beginner" to research-level difficulty. No walled garden: all challenges are free, no subscription needed, and the community publishes solution write-ups once you complete each stage.

CyberDefenders

The blue team answer to Hack The Box — a free training platform built specifically for SOC analysts, incident responders, and DFIR professionals. Labs drop you into real-world attack scenarios (network forensics, malware analysis, cloud incidents) with hands-on artifacts to investigate. Excellent free tier with dozens of beginner-to-advanced challenges.

MITRE ATT&CK

The globally recognized framework that maps real adversary tactics, techniques, and procedures (TTPs) into a structured matrix. Whether you're writing detection rules, doing threat modeling, or building a purple team exercise, ATT&CK is the shared language of the security industry. The website is fully free, browsable, and searchable.

Web Security Academy

Free, browser-based training from the makers of Burp Suite, covering every major web vulnerability class — SQLi, SSRF, auth flaws — with interactive labs you actually exploit rather than just read about.

ANY.RUN

An interactive online malware analysis sandbox — upload a suspicious file or URL and watch it detonate in a real-time virtual machine, clicking through the infection and pulling indicators of compromise.

Hacker101

HackerOne's free video-based web security curriculum paired with an always-on CTF of bug-bounty-style challenges, aimed at anyone breaking into vulnerability research.

pwn.college

Arizona State University's free binary-exploitation and systems-security curriculum, structured as martial-arts-style belts you earn by clearing "dojos" — the intro dojo alone runs 82 challenges. It stays narrower and deeper than the broad CTF platforms: memory corruption, reverse engineering, low-level exploitation, with full lecture videos and slides included for free. Educators can spin up private dojos for a class.

CryptoHack

A gamified crash course in modern cryptography covering modular arithmetic, RSA, elliptic curves, hash functions, and even zero-knowledge proofs across 13-plus categories of interactive challenges. Completely free, with a live scoreboard (the current leader sits north of 9,000 points) and a solve feed you can watch update in real time. Worth a bookmark if every other CTF site feels too broad and you actually want to understand the math.

Trace Labs

A nonprofit that turns OSINT skills toward finding missing people. Its "Search Party" events, held online and at conferences like DEF CON, have participants dig up real leads on real missing-persons cases, then hand what they find to law enforcement. Free to join, funded by donations; the group counts 492 cases assisted and more than 24,000 members so far, plus a free OSINT training VM for practicing before joining a live search.

TryHackMe

A gamified cybersecurity learning platform with guided learning paths that take you from absolute beginner to intermediate penetration tester — browser-based, no setup required. Each module gives you a disposable virtual machine to attack, with hints and a structured lesson around each challenge. "Pre-Security" and "Jr Penetration Tester" paths are fully free and genuinely teach real skills, not just trivia.

OverTheWire

A classic cybersecurity wargame platform where you learn by SSH-ing into remote servers and solving progressively harder challenges. "Bandit" is the recommended start — it teaches Linux fundamentals (file permissions, SSH keys, shell tricks) through 34 levels of increasingly devious puzzles. After Bandit you can progress through Natas (web security), Krypton (cryptography), and Leviathan (reverse engineering). Entirely free, no account needed.

picoCTF

Carnegie Mellon University's free cybersecurity learning platform, built around Capture The Flag challenges spanning cryptography, reverse engineering, web exploitation, forensics, and binary exploitation. The challenges are permanently available in "picoGym" so you can practice at your own pace. Well-structured for beginners with clear difficulty ratings and an active Discord community — many security professionals started their journey here.

Open Source Software

Actual Budget

A local-first, open-source personal finance app using envelope budgeting — you allocate income into spending categories at the start of each month and track how each fills up as you log transactions. All data lives on your device (or your own server) with optional end-to-end encrypted sync; nothing is stored in Actual's cloud. A one-time migration from YNAB takes five minutes. Available as a web app, desktop app, and mobile companion; completely free and self-hostable.

Listmonk

A self-hosted, open-source newsletter and mailing list manager that handles list management, template design, campaign scheduling, subscriber segmentation, bounce processing, analytics, and transactional emails — everything Mailchimp or Sendinblue charge $30-100/month for — at zero cost if you run it on your own server with your own SMTP. Single binary deployable in minutes; supports unlimited lists and subscribers. Used by communities, indie makers, and organizations that need email marketing without the vendor lock-in.

Netdata

A free, open-source real-time monitoring agent that deploys in under a minute (`bash <(curl -Ss https://my-netdata.io/kickstart.sh)`) and immediately begins graphing 2,000+ system and application metrics at per-second granularity — CPU, RAM, disk I/O, network, Docker containers, Kubernetes pods, databases, web servers, and more. Machine learning runs on-device to detect anomalies without cloud dependency. The community tier is fully free; the managed cloud dashboard makes multi-host fleets manageable.

Paperless-ngx

A self-hosted document management system that ingests scanned PDFs, extracts text with OCR, and makes every document fully searchable by content, tag, correspondent, and date. Docker-deployable in minutes — a digital filing cabinet that genuinely works.

AppFlowy

An open-source, local-first alternative to Notion featuring databases, wikis, kanban boards, and rich text documents — your data lives on your machine by default, not locked in a cloud silo. Also self-hostable for teams, or use their hosted version.

Mealie

A self-hosted recipe manager that scrapes recipes from any URL, parses ingredients using ML, and generates weekly meal plans with automatic shopping lists. Runs in Docker and is one of those self-hosted apps that actually earns its keep around the household.

Navidrome

A self-hosted music streaming server that turns your local audio collection into your own personal Spotify — accessible from any browser or the hundreds of iOS/Android apps compatible with the Subsonic API (DSub, Tempo, Symfonium, etc.). Lightweight enough to run on a Raspberry Pi, yet tested against libraries of 900,000+ songs; supports on-the-fly transcoding, multi-user libraries, and scrobbling to Last.fm. Free under GPL; deploys with a single Docker container.

Syncthing

Peer-to-peer, end-to-end encrypted file synchronization that stores your data on your own devices only — no relay server, no cloud account, no vendor. Set it up on two machines, mark a folder to sync, and changes propagate automatically over your local network (or the internet) in real time. Works on Windows, macOS, Linux, Android, FreeBSD, and others; open-source under MPL-2.0. The zero-server model means your files are never stored anywhere you don't control.

FreshRSS

A self-hosted RSS and Atom aggregator that scales from a personal feed reader to a multi-user instance handling 50,000+ feeds and 1M+ articles. Supports web scraping via XPath for sites that don't publish feeds, WebSub for push updates, OPML import/export, and an API compatible with Fever, Google Reader, and Nextcloud News clients — so your existing apps keep working. AGPL-licensed; deploys with PHP or Docker; a hosted demo is available to try before self-hosting.

Forgejo

A community-governed, non-profit git forge — essentially a self-hosted GitHub without the corporate strings. Built as a hard fork of Gitea by the team at Codeberg e.V., Forgejo runs on a single Go binary, handles pull requests, issues, wikis, CI/CD via Forgejo Actions (GitHub Actions-compatible), and a package registry, all on modest hardware.

Dokploy

An open-source self-hosted PaaS that turns a blank VPS into a full Heroku/Vercel/Netlify-style deployment platform in under ten minutes. Point it at a Git repo or Docker image, add your environment variables, and it handles SSL, routing, zero-downtime deploys, and multi-server Docker Swarm scaling. No per-seat fees — just your server costs.

Docmost

A collaborative, self-hosted wiki and documentation platform built as an open-source alternative to Confluence and Notion. Features real-time co-editing, nested pages, full-text search, granular permissions, built-in Draw.io/Excalidraw/Mermaid diagrams, and one-click Confluence/Notion importers. Free to self-host under AGPL with no seat limits.

OneDev

A self-hosted DevOps platform bundling Git hosting, pull requests, CI/CD pipelines, and issue tracking in one app, with built-in code search and AI-assisted merge-conflict resolution.

Postiz

An open-source social media scheduler that plans, AI-generates, and auto-posts content to 30+ networks from one visual calendar — free to self-host, or a paid hosted plan if you'd rather not.

Karakeep

A self-hostable "bookmark everything" app that saves links, notes, images, and PDFs, then uses AI to auto-tag and full-text-index all of it for fast retrieval later.

Kener

Deploy this status page with one Docker command and you're monitoring API, ping, TCP, DNS, and SSL checks within minutes, complete with automatic incident tracking. MIT licensed, built with Svelte.

Immich

A self-hosted Google Photos alternative with 90,000+ GitHub stars and one of the fastest-growing self-hosted communities. Full mobile backup (iOS/Android), facial recognition, timeline browsing, albums, map view, and multi-user support — running on your own hardware with your own storage.

Jellyfin

Fully free, fully open-source personal media server for movies, TV shows, music, live TV with DVR, and photos — no subscription, no tracking, no phone-home. Clients exist for every platform (web, Android, iOS, Apple TV, Fire TV, Roku). The volunteer-driven alternative to Plex that doesn't lock features behind a paywall.

Coolify

A self-hostable open-source alternative to Vercel, Heroku, and Netlify — point it at any server (VPS, Raspberry Pi, bare metal), connect your Git repo, and it handles deployments, SSL certificates, databases, backups, and 280+ one-click services with a clean web UI. Free forever as open source, with an optional managed cloud tier.

Nextcloud

The leading self-hosted Google Workspace alternative: file sync/share across all devices (like Dropbox), calendar and contacts (like Google Calendar), video calls (like Meet), document editing (LibreOffice Online), AI assistant, and 400+ app integrations — all running on your own server with zero data leaving your control. 400,000+ deployments, tens of millions of users. If you run a homelab or a small organization that wants true data sovereignty, Nextcloud is the cornerstone.

ntfy

Send push notifications to your phone or desktop from any script, cron job, or server with a single `curl` command — no app SDK, no OAuth, no API keys for the free public server. Subscribe to a topic on the phone app and `curl ntfy.sh/my-topic -d "backup complete"` from anywhere. Self-hostable on your own server for private use. Eliminates the need for Telegram bots or Slack webhooks for personal automation alerting.

Changedetection.io

A self-hosted website monitoring tool that watches any URL for changes and notifies you via 85+ channels (Discord, Telegram, email, ntfy, Slack, webhooks). Handles JavaScript-rendered pages via Playwright/Puppeteer, supports XPath/CSS selectors to watch only specific page elements (a product price, a stock status, a job posting), and stores a diff history so you can see exactly what changed and when. The open-source answer to expensive commercial monitoring services.

Portainer

A clean, web-based GUI for managing Docker containers, Swarm clusters, and Kubernetes without memorizing CLI commands — deploy containers, manage volumes and networks, view logs, exec into shells, set resource limits, and monitor CPU/memory usage from any browser. The Community Edition is fully free and covers everything a homelab or small team needs; Enterprise adds RBAC and SSO. One `docker run` command deploys it; 30 million+ deployments worldwide.

Windows & Desktop

NirSoft

A one-person software shop by Nir Sofer that has quietly shipped 200+ free, portable Windows utilities since 2001 — Wi-Fi password viewers, browser history exporters, network monitors, process inspectors, registry tools, and more. Every tool is a tiny standalone exe, no installer, no ads, no bundles. An essential bookmark for any Windows sysadmin or power user.

Files

A beautiful, modern file manager for Windows 10/11 that replaces File Explorer with a dual-pane, tabbed interface featuring git integration, cloud storage sidebars, column view, color tags, and a command palette. Free, open source under MIT, and available on the Microsoft Store. If you've ever wished Windows Explorer felt like it was built in this decade, this is it.

Scoop

A command-line app installer for Windows in the spirit of Homebrew — run `scoop install git` and it downloads, extracts, and wires up the app without admin rights, UAC popups, or installer bloat. Everything lands in your home folder. Great for setting up a dev machine fast or keeping tools in sync across machines. Works in PowerShell and is fully open source.

Games & Interactive

Neal.fun

Thirty-plus delightful interactive browser experiments by designer Neal Agarwal: drag your cursor to draw a perfect circle, craft an infinitely recursive universe in Infinite Craft, survive The Password Game's increasingly absurd rules, launch an asteroid and watch it level cities, or spend Bill Gates' money. A playground with no ads and no logins.

Wikitrivia

A free browser card game that pulls historical events from Wikidata's 100 million+ entries and asks you to place them in chronological order on a timeline. Cards cover everything from the founding of ancient kingdoms to the death of scientists. Endlessly replayable, and a surprisingly effective history lesson.

itch.io

The independent game marketplace with thousands of browser-playable free games, pay-what-you-want solo projects, and regular charity bundles. Filters for "Playable in Browser" + "Free" surface an endless stream of creative experiments — from 10-minute narrative games to full jam entries that rival commercial releases.