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Compare two blocks of text and see exactly what changed — line by line.
Drop in two versions to compare
Paste your original and changed text above (or load the sample). Added lines glow green, removed lines glow red.
Differences are computed with a Longest Common Subsequence algorithm, entirely in your browser. Your text never leaves your device.
A diff checker compares two blocks of text or code and highlights exactly what is different between them. It lines up the original and the new version, then marks every added, removed, and changed line so you can review edits at a glance. All of the comparison runs locally in your browser, so nothing you paste is ever uploaded to a server.
A diff checker compares your two inputs line by line (and often word by word within a line). It finds the longest sequence of matching lines, then marks everything else as added or removed so you can see exactly what changed between the original and the new version.
No. The comparison runs entirely in your browser using JavaScript. Nothing you paste is uploaded, stored, or sent to any server, so it is safe to use with private documents, code, and configuration files.
Yes. Paste the contents of two code files into the editors and the tool highlights every added, removed, and changed line. It works with any plain text, including source code, JSON, YAML, logs, and Markdown.
Green marks lines that were added in the new version, red marks lines that were removed from the original, and unchanged lines stay neutral. This added=green, removed=red convention matches the diffs you see in Git and most code review tools.
Compare two blocks of text and see exactly what changed — line by line.
Drop in two versions to compare
Paste your original and changed text above (or load the sample). Added lines glow green, removed lines glow red.
Differences are computed with a Longest Common Subsequence algorithm, entirely in your browser. Your text never leaves your device.
A diff checker compares two blocks of text or code and highlights exactly what is different between them. It lines up the original and the new version, then marks every added, removed, and changed line so you can review edits at a glance. All of the comparison runs locally in your browser, so nothing you paste is ever uploaded to a server.
A diff checker compares your two inputs line by line (and often word by word within a line). It finds the longest sequence of matching lines, then marks everything else as added or removed so you can see exactly what changed between the original and the new version.
No. The comparison runs entirely in your browser using JavaScript. Nothing you paste is uploaded, stored, or sent to any server, so it is safe to use with private documents, code, and configuration files.
Yes. Paste the contents of two code files into the editors and the tool highlights every added, removed, and changed line. It works with any plain text, including source code, JSON, YAML, logs, and Markdown.
Green marks lines that were added in the new version, red marks lines that were removed from the original, and unchanged lines stay neutral. This added=green, removed=red convention matches the diffs you see in Git and most code review tools.