TOOL
Regex Equivalent
Check whether two regexes match exactly the same strings — semantic equivalence via product-DFA analysis, with a shortest counterexample string when they differ. Input: two patterns on separate lines.
Try an example:
Local only
Recent history
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How to use
- Type or paste your input into the input box.
- Adjust any parameters if needed.
- Copy or download the result.
Frequently asked questions
- Is my data uploaded anywhere?
- No. All processing happens locally in your browser with no server round-trip.
- Does this tool work offline?
- Yes. Once the page loads, the tool runs entirely client-side and needs no network connection.
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