Free — instant line-by-line diffText Diff Checker
Compare two blocks of text with red and green highlighted differences. Instant, private, free.
Original
Modified
Line-by-Line
LCS-based diff algorithm for accurate line-level comparison.
Color Coded
Green for additions, red for removals. Clear at a glance.
Private
All comparison runs locally. Your text is never uploaded.
Frequently asked questions
What algorithm is used?
The diff uses the Longest Common Subsequence (LCS) algorithm for accurate line-level comparison, the same approach used by Git.
Can I compare code?
Yes! The monospace font and line numbers make it ideal for comparing code, configuration files, and any structured text.
Is there a size limit?
No hard limit, but very large texts (10,000+ lines) may be slower. For best performance, keep comparisons under a few thousand lines.
Is my text stored anywhere?
No. All comparison happens locally in your browser. Nothing is sent to any server.