Code Diff Online

Compare source code files side by side and find differences instantly.

ORIGINAL1 lines
MODIFIED1 lines

What Is Code Diff?

Code Diff is a free online tool that compares two snippets of source code side by side, highlighting every added, removed, or changed line. It works with any programming language — JavaScript, TypeScript, Python, Go, Java, C++, Rust, and more — making it the perfect code comparison tool for developers.

How to Use Code Diff

  1. Paste your original source code into the left panel.
  2. Paste the modified source code into the right panel.
  3. Click Compare to view the highlighted diff.
  4. Toggle between Split and Unified view to review changes.

Features

  • Works with any programming language
  • Split and unified diff views
  • Line number display
  • Added / removed line counters
  • Copy diff result to clipboard

FAQ

Which languages does Code Diff support?

Code Diff is language-agnostic — it compares any plain text, so it works with every programming language.

Is there a file size limit?

No server-side limits. Large files are processed entirely in your browser.

Can I use Code Diff to review pull request changes?

Yes. Paste the old version on the left and the new version on the right to get an instant diff.