Text Diff Checker
Compare two texts and highlight the differences
How it works
- 1Paste original text
Drop the first version into the left panel.
- 2Paste new text
Drop the updated version into the right panel.
- 3See the diff
Added lines appear green, removed lines red, unchanged lines gray.
About Text Diff Checker
Free online text diff checker. Paste two texts side by side to see additions, deletions, and unchanged lines highlighted. Perfect for comparing code, configs, contracts, or any two versions of a document. Runs entirely in your browser. Text Diff Checker on 712 Tools runs entirely inside your browser using modern JavaScript APIs — no server ever sees your data. That means instant results, complete privacy, and no upload limits.
Whether you need to compare two texts and highlight the differences for a debugging session, a quick sanity check, or a production incident, this tool is free to use as many times as you need. There are no watermarks, no sign-up, and no ads inside the tool itself.
Frequently asked questions
Is it a line diff or a character diff?
This tool does a line-by-line diff using the Myers algorithm. That's the standard for git and most code review tools.
Does it handle very large files?
Yes — up to your browser's memory. Files over a few megabytes may take a second or two to render.
Is my text uploaded anywhere?
Never. Diffing runs entirely in your browser. Neither version leaves your device.
Can I export the diff?
Copy the highlighted output as plain text — the +/- prefixes match unified-diff format for pasting into commits or reviews.
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