Pattern and text
\w+@\w+\.\w+ against help@uuup.dev
Result
Matches help@uuup.dev
Developer Tools
Regex Highlight Tester — JavaScript Pattern Matching
Test JavaScript regular expressions in your browser with native RegExp. Supports flags such as i, g, and m, highlights matches, and shows capture groups with offsets for debugging email, crawler, and validation rules.
RegexTestingHighlight
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开发工具
Regex Highlight Tester
/ /
Flags
Target Text
Match Results
Powered by JS RegExp Engine Native execution. Some PCRE features (like lookbehinds in old Safari) might not be fully supported.
Use cases
- Debug email or URL validation patterns
- Check whether greedy matching runs past the intended span
- Inspect capture group text and match positions
How to use
- Enter a regular expression and choose flags
- Paste the text to test
- Review highlighted matches and capture groups
Example input and output
FAQ
Which syntax is supported?
It follows the browser native RegExp implementation. Advanced features such as lookaround depend on the current browser.
Does the test text leave the browser?
No. Matching runs locally in your browser.
Tools
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