Everything in the catalog

Free scorewriter for notating Byzantine chant in Byzantine notation.

Self-hosted workout tracker with an AI coach that knows your training.

Write MicroPython for the BBC micro:bit and flash it over WebUSB.

Nepali tiger-and-goats strategy board game playable in the browser.

Visual music theory site that shows harmony as colored flags and piano-roll views of songs.

Kanban-style board for managing tasks in columns, running in the browser.

Procedural dungeon generator that builds a room graph and lays it out into a map.

Browser calculator that handles decimals, negative values and percentages.

Classic Fifteen sliding puzzle mini-game in the browser.

Free CV Maker with Print-Friendly Responsive Layout

Online developer toolbox with 146 tools for formatting, encoding, hashing, network lookups, text processing and colors.

Generate a polished, professional resume in just a few clicks with this AI-powered resume builder.

Generates QR codes with a GitHub logo for profiles and projects and exports SVG, PNG, JPEG or WebP.

Calculates optimized subnet masks for a list of host-count requirements.

Browser QR generator that overlays a logo, adds UTM campaign parameters and exports PNG or SVG up to 1200 px.

Colorful tile-laying game where matching colors create shapes and fill the board.

Datasette running in the browser through WebAssembly to explore SQLite and CSV files.

Generates digital business cards with a QR code.

Markdown editor web app that edits local files through the File System Access API, with optional in-browser AI.

Web app for building crosswords with autofill, themed entries and export formats for publishing.

Toolbox with text processing, code formatting, regex testing, encoding, hashing and other web utilities.

Hosted GraphiQL that connects to any GraphQL endpoint URL you supply.

M餐搭子：基于麦当劳 MCP 实时菜单与营养数据的智能搭餐 Skill｜在线演示已上线

Editor for jianpu numbered notation and staff notation with live preview and transposition.