Q3Edit is a browser-based level editor for Quake 3 that mimics Radiant. It supports brush and patch editing, CSG, terrain sculpting, and entity editing. Files open and save as .map file and can be played directly in the browser using a WebAssembly build of ioquake3.

The editor runs in TypeScript + WebGL2 and compiles maps with the original q3map from id Software compiled to WASM. One click launches the map in the browser-native engine, so no game files are required. It ships with Open Arena assets and needs a WebGL2-capable browser.

Q3Edit offers a four‑view UI like Radiant, giving users full control over geometry and textures. The integration of q3map and ioquake3 in WASM makes compilation and playback instant, letting designers test changes in real time.

The project demonstrates that complex game level editing can run fully in the browser, opening new possibilities for web‑based game development and collaborative map creation. Users can share their maps directly via URLs, simplifying collaboration and deployment across platforms.