Text Diff Checker
Compare two blocks of text and highlight the differences.
About the Text Diff Checker
Compare two blocks of text and highlight the differences line by line. Free online text comparison tool.
Why client-side?
Every byte you paste, type, or upload here is processed entirely inside your browser. Nothing is sent to a server, logged, or stored. That means it's safe to use this tool on production secrets, customer data, internal logs, and any input you would not paste into a hosted SaaS formatter.
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Frequently Asked Questions
- How do I compare two texts?
- Paste the original text on the left and the modified text on the right. The tool highlights additions, deletions, and changes between the two versions.
- Can I compare code files?
- Yes. The diff checker works with any text including source code. It compares line by line and highlights all differences.
- Does this tool handle large texts?
- Yes. The diff checker runs in your browser and can handle large text comparisons efficiently.