Text Diff Checker

Paste two versions of a text and see exactly what changed — added lines, removed lines, and everything that stayed the same. Great for comparing drafts, code, configs, or documents. Nothing is uploaded.

How the comparison works

The tool compares the two texts line by line using a longest-common-subsequence diff — the same idea behind version-control tools like Git. Lines only in the original are marked as removed, lines only in the changed version are marked as added, and unchanged lines are shown plainly. It's the fastest way to see what moved between two versions.

What it's good for

Everything runs locally in your browser, so even sensitive text stays on your device.

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Frequently asked questions

Does it compare word by word or line by line?

Line by line, which is the clearest way to see structural changes. Whole lines are marked added, removed, or unchanged.

Is my text uploaded anywhere?

No. The comparison runs entirely in your browser and nothing is sent to a server.

Can I compare code?

Yes — it works for any plain text, including code and configuration files.