Developer Tools

Text Diff

Compare two texts side-by-side with character-level highlighting -- all in your browser.

100% local
Runs in your browser
Zero sent
No tracking, no servers
Paste text in both panels and click Compare to see the diff.

How to Use

  1. 1
    Paste original text into the left panel -- this is your baseline.
  2. 2
    Paste modified text into the right panel -- this is the updated version.
  3. 3
    Click Compare to generate a color-coded diff. Green lines are additions, red lines are removals.
  4. 4
    Toggle options -- switch between side-by-side and inline views, ignore whitespace or case differences, swap sides, or copy the diff.

Frequently Asked Questions

How does the text diff work?
The tool uses the Myers diff algorithm (via the jsdiff library) to compute the minimal set of changes between your two texts, then renders the result as a color-coded diff. Green highlights show additions, red highlights show removals.
What is character-level highlighting?
Character-level highlighting shows exactly which characters changed within a modified line, not just that the line was changed. This makes it easy to spot small edits like typos or single-word changes.
Can I use this to diff code?
Yes. The tool works with any plain text including source code, configuration files, JSON, CSV, and more. The diff output includes line numbers and supports syntax-aware word matching.
Is my data stored anywhere?
No. All processing happens entirely in your browser using JavaScript. Your text is never sent to any server.
What do the colors mean?
Green backgrounds indicate text that was added in the modified version. Red backgrounds indicate text that was removed from the original. Within changed lines, darker highlights show the specific characters that differ.