Regex Tester
Test JavaScript regular expressions live with highlighted matches, a capture group table and a replace preview.
Runs in your browserRegex → Matches
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How to use the Regex Tester
- Paste or type your Regex into the input area, or open a file from your device.
- Adjust the options above the editor if the tool offers any.
- Review the Matches result, then copy it or download it as a file.
Privacy and limitations
- Your data is processed on your device and is not uploaded to any server.
- Uses your browser's JavaScript regex engine. Test text is limited to 50,000 characters and 1,000 matches; patterns with catastrophic backtracking can still be slow.
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