about compResso.
compresso is a browser-based video compression tool. drop in a video file, pick a codec and quality level, and get a smaller file back. the whole thing runs locally — ffmpeg.wasm processes your video directly in the browser using webassembly.
no file ever leaves your device. there is no server, no cloud storage, and no account. once ffmpeg.wasm is loaded (from cdn the first time), it works entirely offline.
why it exists
most video tools either upload your file to a server or require installing software. compresso does neither. it is a single web page that compresses video privately and directly, in whatever browser you have open.
tech stack
- next.js 16app router, typescript, static generation
- ffmpeg.wasm@ffmpeg/ffmpeg 0.12 — runs ffmpeg in the browser via webassembly
- tailwind css v4utility-first styling with custom design tokens
- vitestunit and component testing with @testing-library/react
browser compatibility
compresso requires SharedArrayBuffer, which is only available in cross-origin isolated contexts. the correct COOP/COEP headers are set automatically.
works in chrome 92+, firefox 79+, and safari 15.2+. safari on ios requires ios 15.2 or later.