Regex tester
Test and debug regular expressions with live matching
Regular expression
//g
Flags:
Quick patterns
Test string
Test regular expressions with live matches
Free online regex tester. Test, debug and validate regular expressions with live match highlighting, group capture and quick patterns.
Live regex matching
Enter a pattern, choose flags and paste a test string to see matches update instantly. It is useful for validating emails, URLs, IDs, logs and extracted text.
Capture groups and flags
Review match positions and capture groups, then copy the complete regex with its flags when you are ready to use it in code.
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Frequently asked questions
Which regex engine does this use?
The tester uses JavaScript regular expressions in your browser, so results match modern JavaScript behavior.
Can I test regex capture groups?
Yes. Use the Groups tab after entering a pattern with parentheses to inspect captured values.
Does the regex tester run privately?
Yes. Patterns and test strings are processed locally in the browser.