Everything in the catalog

Open-source mind mapping app that offers collaborative maps and sharing.

Local-first virtual tabletop for hosting games, inviting players and keeping character sheets and scenes.

Relational algebra calculator for learning by executing RelAlg queries.

Generates a fluid type scale as CSS clamp() variables.

Parses binary files using a .ksy format description and shows the decoded object tree beside a hex view.

Shows how overpayments cut mortgage term and interest, charted with D3.

Talks to serial devices such as Arduinos from the browser using the Web Serial API.

Simulation of simple particles attracted and repelled by color rules that form lifelike structures.

Builds perceptually even color scales and checks them for color blindness.

Estimates carbon emissions from training a machine learning model based on GPU, hours and region.

Abstract board game written in Rust and WebAssembly, playable online.

Local-first, privacy-focused resume builder that runs entirely in the browser, with a Chinese interface.

Creates diceware passphrases in the browser with a choice of word lists and entropy display.

Open-source Wordle with infinite, hourly and daily modes and a tap-to-define feature for each guessed word.

Draws electronic circuits and animates current and voltage in real time.

Markdown viewer and editor that renders your text in real time in the browser.

Live-coding environment for networked video synth visuals written in JavaScript.

Run and share Swift snippets in the browser.

Light-weight General MIDI synthesizer and MIDI player written in WebAudio JavaScript, with a keyboard demo.

Computes UK capital gains from broker transaction exports and produces a PDF report for self assessment.

Play a 3D Rubik's Cube in the browser with drag controls and a built-in timer.

Browser music tracker driving a built-in synthesizer, for composing patterns and sharing songs.

Scans a site for third-party requests, cookies, security headers and other privacy issues.

Financial derivatives calculator with 171+ models including Black-Scholes.