Text Diff Checker
Compare two texts side by side — see exactly what changed, line by line.
Writers, developers and editors constantly need to see what changed between two versions of a text. This diff checker runs entirely in your browser.
How to use
- Paste the original text into box A and the modified version into box B.
- Optionally tick "ignore whitespace" or "ignore case" for a cleaner diff.
- Click Compare — additions show in green, deletions in red, with word-level highlights.
About this tool
Changed lines are paired automatically, and the exact changed words inside them are highlighted — so you spot edits at a glance.
Frequently asked questions
Is there a size limit?
The diff engine handles up to about 5,000 lines per side. For very large documents, compare them in smaller chunks.
What does "ignore whitespace" do?
It collapses multiple spaces/tabs and trims trailing whitespace before comparing, so pure formatting changes don't show as differences.
Is my text uploaded anywhere?
No. The comparison runs 100% in JavaScript on your device. Nothing leaves your browser.
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