Diff Checker

Side-by-side text comparison. Highlights additions, deletions, and unchanged lines.

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Your files never leave your device
Lightning fast
Optimised for speed
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Use instantly, no account

Paste two versions of text below — the original (before) on the left and the changed (after) on the right. The diff appears underneath.

Original · before
Changed · after
Diff

Paste text on both sides to compare.

Compare two pieces of text and see exactly what changed — line by line, word by word, or character by character — with clear additions and removals. Ignore case or whitespace and get a quick count of the changes.

How to use Diff Checker

  1. 1Paste the original text on the left and the changed text on the right.
  2. 2Choose Lines, Words, or Characters granularity.
  3. 3Optionally ignore case or whitespace.
  4. 4Read the highlighted diff with added/removed counts.

Frequently asked questions

Yes. Switch to Words or Characters for GitHub-style inline highlighting that pinpoints exactly what changed within a line.
Yes — toggle “Ignore case” and “Ignore whitespace” to focus on meaningful changes only.
No. Everything runs entirely inside your browser using your own device — your files never leave your computer or get uploaded anywhere. That makes it private and fast, even for large files.
Yes, completely free with no sign-up, no watermark, and no daily limits. Use it as much as you like.

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