Diff Checker

Compare two texts and highlight the differences.

What is Diff Checker?

Diff Checker compares two texts line by line and highlights additions, removals, and unchanged lines. Shows similarity percentage, added/removed line counts, and a color-coded diff view like GitHub.

How to use this tool

  1. Paste two texts separated by a line containing only ---.
  2. Click Compare to see the diff.
  3. Green lines (+) are additions, red lines (-) are removals.
  4. Check the similarity percentage at the top.
  5. Use for comparing code versions, config files, or any text.

Frequently asked questions

How do I separate the two texts?
Put the first text, then a line with just three dashes (---), then the second text. The tool splits on this separator and compares line by line.
What does similarity percentage mean?
The ratio of unchanged lines to total lines. 100% means identical, 0% means completely different. Useful for quickly assessing how much changed between versions.
Can I compare code files?
Yes, it works with any text including source code, JSON, XML, CSV, and configuration files. Syntax highlighting is not applied but the line-by-line diff works for all formats.
How is this different from git diff?
Git diff uses a sophisticated algorithm (patience, histogram) that groups related changes better. This tool does a simpler line-by-line comparison which is sufficient for quick checks without needing git installed.

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