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Text Diff Checker

Compare two texts and find differences online

About Text Diff Checker

Compare two texts side by side and see the exact differences highlighted. Uses an LCS (Longest Common Subsequence) algorithm to accurately identify added, removed, and unchanged lines. Copy the unified diff output for use in code reviews, documentation, or version comparison.

Use Cases

  • Comparing two versions of a configuration file
  • Finding changes between code revisions
  • Checking differences in API responses
  • Comparing document drafts for editorial review

Frequently Asked Questions

How does the diff algorithm work?

This tool uses the Longest Common Subsequence (LCS) algorithm to find the optimal alignment between two texts, then marks lines as added, removed, or unchanged.

Can I compare code?

Yes. The diff checker works with any text including code, configuration files, JSON, CSV, and plain text documents.

What do the colors mean?

Green (+) indicates lines that were added in the modified text. Red (-) indicates lines that were removed from the original. Unmarked lines are identical in both.

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