Text Diff Checker
Last updated: June 1, 2026Compare two texts line by line.
Text Diff Checker is a free online tool to compare two texts line by line. It runs entirely in your browser, so your files never leave your device — nothing is uploaded. There's no sign-up, no watermark, and it works on any modern browser on desktop or mobile.
How to use Text Diff Checker
The Text Diff Checker compares two blocks of text and highlights exactly what was added and removed, line by line. It's great for comparing code, contracts, drafts and config. Runs entirely in your browser — nothing is uploaded.
- 1Paste the original text on the left.
- 2Paste the changed text on the right.
- 3Read the highlighted line-by-line differences.
Clear line diff
Added lines in green, removed in red, with a summary count.
Any text
Compare code, documents, lists or config side by side.
Private
Both texts stay on your device — nothing is uploaded.
Text Diff Checker — frequently asked questions
How does it compare the text?
It uses a longest-common-subsequence diff on the lines, so it finds the minimal set of additions and removals between the two versions.
Can I compare code?
Yes — it's line-based and monospaced, which works well for code, JSON and config files.
Is my text uploaded?
No — the comparison runs entirely in your browser.
Is it free?
Yes, completely free.
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