Side-by-Side Text Diff
Paste or upload two versions of any text and see them compared column by column, original on the left, updated on the right. Added, removed, and changed lines are colour-coded and aligned so your eye can scan straight across to spot every difference. Useful for reviewing edits to prose, translations, configuration files, and code. All processing runs in your browser.
How it works
The diff algorithm runs in a Web Worker inside your browser, so the page stays responsive even for large files. All processing runs locally.
Processing runs in your browser
All diffing is done locally using browser APIs. Our servers are not involved at any point.
Related operations
For making the same change everywhere in one file, try find and replace. To put both inputs in matching order before comparing, use sort lines. For diffing two JSON payloads after pretty-printing, see the JSON formatter.