Private Offline Text & Code Diff Checker

Compare two blocks of code, config files or legal contracts side-by-side with word-level highlighting. Runs 100% in your browser - nothing is uploaded or stored.

LCS Text & Code Diff Checker

Line-by-line and inline word-level diffing — 100% private in your browser

4 lines
4 lines
+0 added-0 removed~4 modified0 unchanged
1The quick brown fox jumps over the lazy dog.
1The fast brown fox leaped over the lazy dog.
2Pikden is fast and private.
2Pikden is extremely fast and 100% private.
3Legacy line that was removed.
3Built for modern creators.
4Built for creators.
4Added a brand new closing line.

How to compare two texts privately

  1. Paste the original version on the left and the revised version on the right.
  2. Toggle "Side-by-Side" or "Unified" view, and check "Ignore Whitespace" or "Only Changes" if needed.
  3. Inspect inline word-level additions and deletions, or click "Copy Diff Patch" to export a unified diff.

Why use an offline diff tool?

Developers regularly compare .env files, production configs, SQL dumps and proprietary source code; lawyers and editors compare redlined NDAs and unpublished drafts. Pasting that text into a server-backed diff site risks logging sensitive secrets. This tool computes the Longest Common Subsequence (LCS) and word-level diff entirely inside your browser memory.

Frequently asked questions

Does it highlight word-level changes inside a modified line?

Yes. Paired modified lines are tokenized and compared at the word level so you can spot a single changed variable or typo immediately.

Can I ignore whitespace or capitalization differences?

Yes. Enable "Ignore Whitespace" or "Ignore Case" in the toolbar to filter out formatting noise.

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