Text Diff Checker

Spotting what changed between two versions of a contract, a config file, or a draft is slow and unreliable by eye. This diff checker aligns the two texts line by line and colours additions, deletions, and matches, so the actual change stands out immediately.

How to use it

  1. Paste the original version into the left box.
  2. Paste the modified version into the right box.
  3. Read the combined diff: green for added lines, red for removed, plain for unchanged.
  4. Check the summary counts to see the scale of the change at a glance.

Frequently asked questions

Does it compare word by word or line by line?

Line by line, using a longest-common-subsequence alignment. That is the standard approach for documents and code and keeps the output readable.

Why does one small edit mark the whole line as changed?

Because a line is the unit of comparison. A single altered word marks its line as removed and re-added, which is how version control diffs behave too.

Can I compare code with it?

Yes. Indentation and blank lines are preserved exactly, so source files, YAML, and JSON all compare cleanly.

Is anything uploaded?

No. The comparison runs entirely in your browser, so you can safely diff private or unreleased material.

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