Text Diff Checker
Compare two texts side by side and find differences instantly. Free online diff tool — highlight additions, deletions, and changes.
How to Use the Diff Checker
Paste the original text on the left and the modified version on the right, then click "Compare". Additions are highlighted in green, deletions in red.
Frequently Asked Questions
How does the diff checker work?
It uses a longest common subsequence (LCS) algorithm to compare two texts line by line. Lines present only in the original are marked as deletions (red), lines present only in the modified version are marked as additions (green), and unchanged lines are shown in gray.
Is this diff checker free?
Yes, completely free with no limits. No signup or account required. All comparison is done locally in your browser — nothing is sent to any server.
Can I compare code with this tool?
Yes. The diff checker works with any plain text including source code, configuration files, HTML, JSON, and more. It compares line by line, making it suitable for reviewing code changes.
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