Text Diff Checker
Compare two texts and see the differences highlighted line by line. Find additions, removals, and changes instantly.
About This Free Online Text Diff Checker
Our free online Text Diff Checker compares two blocks of text and highlights every difference. See added lines in green, removed lines in red, and changed lines in yellow — just like a professional diff tool. Perfect for reviewing document changes, comparing code versions, checking edits, or verifying text before and after processing. Line-by-line comparison makes it easy to spot exactly what changed. All processing is done in your browser for complete privacy.
Features of Our Text Diff Checker
- Line-by-line diff comparison
- Added lines highlighted in green
- Removed lines highlighted in red
- Changed lines highlighted in yellow
- Word-level highlights within changed lines
- Copy both versions easily
- 100% private — browser-only processing
How to Use the Text Diff Checker
Using this tool is simple and requires no signup or registration. Follow these steps:
- Paste the original text into the left textarea.
- Paste the modified text into the right textarea.
- View the diff result with color-coded changes.
- Use the action buttons to copy either version.
Frequently Asked Questions About Text Diff Checker
How does the diff algorithm work?
The tool uses a line-by-line Longest Common Subsequence (LCS) algorithm for accurate diff output. Lines are classified as added, removed, unchanged, or changed.
Can I diff code with this tool?
Yes. The tool works with any text including code, making it useful for reviewing code changes and pull request diffs.
Is my text sent to any server?
No. All diff computation happens entirely in your browser. Nothing is uploaded or stored externally.
Why Choose Text Toolbox?
Text Toolbox provides free, private, and instant online text tools. Unlike other text utility websites that require signup accounts or send your data to servers, all our tools process your text entirely in your browser. This means your content never leaves your device — we cannot see it, store it, or share it. Our tools are fast, lightweight, and work on any device with a modern web browser.