Text Diff Checker
Compare two texts side by side and highlight the differences. Supports inline and side-by-side views with line-level and character-level diff detection.
How to Use the Text Diff Checker
Paste your original text in the left panel and the modified version in the right panel. The diff checker instantly highlights additions, removals, and unchanged lines using a standard line-by-line comparison algorithm similar to the Unix diff command.
What Is a Text Diff?
A text diff (short for "difference") shows what changed between two versions of a document. Developers use diff tools daily to review code changes, compare configuration files, and verify edits before committing. Writers use them to track revisions in contracts, articles, and drafts. Our tool processes everything locally in your browser — your text never leaves your device. For comparing structured data, try our JSON formatter to pretty-print JSON before diffing.
Common Use Cases
Compare two versions of a code file before merging. Spot changes in legal documents or contracts. Verify that a search-and-replace operation only changed what you intended. Compare API responses from staging and production. Track changes in translated documents across languages. Pair it with our word counter to measure how edits affect document length. The side-by-side view is ideal for reviewing long documents, while inline mode provides a compact view for quick scans.