Content and text
Text Diff Checker
Paste two versions of a text and see exactly what was added and removed.
Runs in your browser; nothing is uploaded. · Free, no account · 2 min
Importing a saved run into your account is coming soon. Until then, your last runs stay in this browser only, and you can download your files.
How to use
- Paste the original text in the left box and the changed text in the right box.
- Choose to compare by lines, words or characters.
- Tick the options to ignore case, or spaces at the ends of lines.
- Read the added and removed counts, then copy the diff.
What it checks and how it works
The comparison uses the jsdiff library, an implementation of the Myers O(ND) difference algorithm, which finds the shortest list of additions and removals that turns one text into the other. By lines, the result is written in the unified format described in the POSIX diff specification, with three lines of context around each change. By words or characters, changes are marked inline: [-removed-] and {+added+}.
A diff shows differences, not meaning: moving a paragraph reads as one removal and one addition. Line mode ignores only the spaces at the start and end of a line, not spaces inside it.
Sources
- POSIX: diff utility (unified output format) opened 29 Oct 2026
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Questions
About this tool
Line mode suits files and lists. Word mode suits edited prose, and character mode shows small changes such as a typo or a changed digit.
Yes. Arabic is compared as Unicode text, and the output follows the direction of the text. A small spelling change, such as hamza on an alef, shows as a change.
Yes, as text. Format both versions with the JSON formatter first so that spacing differences do not drown out real changes.
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