DEVELOPER TOOLS
Text & Code Diff Checker
Compare two versions line by line. Added, removed, and unchanged lines are shown locally in your browser; your text is not uploaded or saved.
Original text stays here, even when comparison options are enabled.
The comparison updates shortly after either editor changes.
Comparison
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Modified
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How this comparison works
This is a line-based comparison for reviewing text, code edits, drafts, or configuration changes. It uses a Myers shortest-edit-script algorithm, so insertions and deletions are matched across the surrounding lines instead of comparing only lines at the same positions. Repeated lines are matched in their original order. Side-by-side rows keep inserted or removed lines on their own side rather than pairing unrelated lines.
Each newline separates a line; a trailing newline is represented by a final blank line. Whitespace ignoring removes whitespace characters from line content for matching, and case ignoring compares lowercase forms. These options affect matching only: the editors and displayed lines retain the text you entered. This tool compares whole lines, not individual characters or programming-language syntax.
Comparison runs locally. Each input is limited to 250,000 characters and 10,000 lines, with an additional work limit for highly divergent text so the page can remain responsive. If a comparison exceeds a limit, split the material into smaller sections.