How does the diff algorithm work?

It uses a longest common subsequence (LCS) algorithm to find the minimal set of changes between the two texts, similar to how git diff works.

Yes. The diff checker works with any text including code, prose, configuration files, and data. It compares line by line.

Is there a size limit?

No hard limit, but very large texts (10,000+ lines) may slow down in the browser. For typical use cases it's instant.

Developer Tool

Text Diff Checker

Compare two texts and see the differences highlighted line by line. Added lines in green, removed in red, unchanged in gray. See stats for lines added, removed, and unchanged.

100% free — no account needed

Original Text

Modified Text

See Every Change

Visual line-by-line comparison with color coding

Line-by-Line Diff

Compare two texts and see exactly which lines were added, removed, or kept.

Color Coded

Green for additions, red for removals, gray for unchanged lines.

Line Numbers

Each diff line shows its line number for easy reference.

Change Statistics

See total lines added, removed, and unchanged at a glance.

FAQ

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