Test regular expressions against sample strings with live match results. Set pattern, flags, and test text to see matches, groups, and match count instantly.
0Matches
—Pattern status
Enter a pattern and test string.
Frequently Asked Questions
Which regex flavor is used?
JavaScript RegExp — the same engine used in browsers and Node.js.
What flags are supported?
g (global), i (case-insensitive), m (multiline), s (dotall), u (unicode), and y (sticky).
Can I test capture groups?
Yes. Group values appear in the match details when your pattern includes parentheses.
Is my data sent anywhere?
No. All matching runs locally in your browser.
Is this tool free and does it work on mobile?
Yes on both counts. The Regex Tester on draft21 is completely free with no sign-up required and works on all devices.