Text diff checker

Compare two texts and highlight added and removed lines.

Runs on your deviceFreeNo account

How to use Diff checker

Paste original text on the left and changed text on the right. The diff highlights deletions and additions. Use it for contract redlines, config drift, or writing edits. Copy the patch if you need a unified diff.

A side-by-side (and inline) diff for copy, code, and config files. Built on the classic Myers diff. Nothing is sent to a server.

Also searched as diff checker, compare text, text difference. All processing for this tool happens in your tab unless labeled otherwise.

Questions

Word vs line diff?

The default is line-based, with word-level highlighting inside changed lines.

File upload?

Yes — load two text files if you would rather not paste.

Binary files?

Not supported. Use a hash comparison for binaries.

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