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Client-sidefiles never upload

Text Diff (line-by-line)

Paste two texts; LCS computes a line-by-line diff with **added / removed / changed** colour-coded. Toggle to **ignore whitespace** or **ignore case**, export as **unified diff** (git / patch compatible).

added 1removed 0changed 1unchanged 3
LLeft (before)RRight (after)
1apple1apple
2~banana2blueberry
3cherry3cherry
4date4date
+5elderberry
β€ΊHow to use
  1. Paste the old version on the left and the new on the right (empty input counts as 0 lines).
  2. The side-by-side table updates live: + green insert, βˆ’ red delete, ~ amber replace (adjacent delete+insert merged), grey = unchanged. Both line numbers (L / R) shown.
  3. (Optional) toggle Ignore whitespace to collapse runs of spaces, or Ignore case to compare case-insensitively β€” great for checking 'did anything substantive change' after a formatter.
  4. Copy unified diff for a git / patch-compatible blob you can drop into a PR description, Linear, Slack.
Tips
  • LCS (Longest Common Subsequence) is the algorithm behind git diff, O(nΓ—m). 1000 Γ— 1000 lines finishes in <10ms.
  • Replace = delete + insert merging β€” adjacent removals + insertions are treated as a 'line was changed' for a more intuitive read.
  • Ignore whitespace is great for checking 'did prettier change anything meaningful'.
  • vs diffchecker.com β€” they paywall ignore options; we're free + no upload.

πŸ’‘ Diff runs entirely in the browser (the JS LCS is fast enough). No upload β€” fine for contracts, confidential docs.

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