Text Diff
Paste the original and the changed text; see exactly which lines were added and which were removed. The comparison runs on a real longest-common-subsequence algorithm, in your browser.
Differences
Paste both texts and press Compare.
What "a real diff" means here
Naive comparisons line the two texts up from the top and flag everything that mismatches, which reports huge fake changes when one line is inserted early on. This tool computes the longest common subsequence of the two line lists - the same core algorithm behind git diff - so a single inserted line shows up as exactly one addition, and the rest of the text stays matched.
Where a line diff earns its keep
- Reviewing copy edits. A marketing rewrite of a product page: see at a glance whether claims were quietly changed, not just reworded.
- Checking config and .env examples. Compare a documented example against your working file to find the one line that differs - usually the bug.
- Verifying an export. Re-run a data export and diff it against yesterday's to confirm only the expected rows changed.
For character-level edits inside one long paragraph, a line diff shows the whole paragraph as changed; paste the paragraph in, split manually, or use the ignore-whitespace option to skip indentation noise.
Frequently asked questions
Is my text uploaded?
No. The diff is computed entirely in your browser's JavaScript. Contracts, drafts and configs never leave the device.
How large can the texts be?
Thousands of lines are fine; the algorithm is O(n×m), so two 10,000-line documents will take a moment but still work in a normal browser tab.
What do the symbols mean?
Lines starting with + exist only in the changed text; lines starting with − exist only in the original; unchanged context lines are shown dimmed.
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