Text Diff
Free Local ProcessingFree online text diff tool that compares two pieces of text line by line using the longest common subsequence (LCS) algorithm, clearly marking added and deleted lines. Supports ignore-case and ignore leading/trailing whitespace. All processing happens in your browser, content never uploaded, privacy-safe.
Options
How to Use
- 1 Type or paste the original text in the input box
- 2 Enter the modified content in "Modified text"
- 3 Optional: check "Ignore case" or "Ignore leading/trailing whitespace" to focus on real changes
- 4 Click "Start Compare" button
- 5 View the diff result. Added lines are marked with "+", deleted lines with "-"
FAQ
Q: Is text uploaded to the server?
No. Both pieces of text are compared in your browser. Content never leaves your device.
Q: What algorithm is used for comparison?
Uses a line-by-line comparison algorithm based on the longest common subsequence (LCS), which accurately identifies added and deleted lines.
Q: What does ignore case/whitespace do?
When checked, the comparison ignores letter case differences or leading/trailing whitespace, making it easier to focus on substantive content changes.
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