Text Diff Checker
Paste or type two versions of a text below, then click Compare to see what changed. Added lines are highlighted, removed lines are marked, and a summary shows the total changes.
Click "Compare" to see differences…You might also need.
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About this tool
The Text Diff Checker compares two blocks of text line by line and highlights every difference. Writers use it to track changes between drafts before handing copy to an editor. Developers compare configuration files, log outputs, or code snippets to spot what changed between versions. Editors verify that requested revisions were applied correctly without introducing unintended modifications. The tool uses a Longest Common Subsequence (LCS) algorithm to accurately detect added, removed, and unchanged lines, even when large blocks are rearranged. Three comparison options — Ignore Case, Ignore Whitespace, and Ignore Empty Lines — let you focus on meaningful differences. Everything runs in your browser; no text is ever uploaded or stored.