The fastest diff on the web.

Rust → WebAssembly · runs entirely in your browser · nothing is ever uploaded

ORIGINAL 0 chars · or drop a file

drop file to load

CHANGED 0 chars · or drop a file

drop file to load

// nothing you paste or drop ever leaves this tab — the diff runs locally

loading engine…

+0 −0 paste text above to see the diff

Milliseconds, not seconds

Myers diff implemented in Rust, compiled to WebAssembly. A 5,000 line file diffs in about 10 ms, measured around the engine call, so the result updates live on every keystroke.

code snippet (the example)0.1 ms

5,000 line file (150 KB)10.1 ms

medians of 50 runs on committed fixtures: scripts/bench-vs-js.mjs

Your text never leaves the browser

100% client-side. No uploads, no servers, no logs. Diff contracts, source code, or anything confidential with zero exposure. Works offline once loaded.

Open source core

The Rust diff engine is MIT-licensed. Audit it, embed it, or use it via the upcoming Diff API.

$ cargo add diffwtf-core