Online Text Diff Tool
Compare two texts line by line with char-level highlighting and stats. 100% private, all processing in your browser
Frequently Asked Questions
The tool uses the LCS (Longest Common Subsequence) algorithm for line-by-line comparison, then highlights character-level changes within modified lines.
No. All comparison is done locally in your browser. Your text never leaves your device, fully protecting your privacy.
Green marks added lines, red marks removed lines, amber marks modified lines with inline char-level highlights, and gray marks unchanged lines.
Yes. Toggle options to ignore empty lines, ignore case, or trim whitespace before comparing, useful for formatting-insensitive diffs.
It handles fairly large inputs, but the LCS algorithm has O(n*m) complexity. For best performance, avoid comparing extremely long documents.
Completely free. This is a pure frontend online tool - no registration required, no payment needed, just open and use.
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