regex tester

Test a regex.

Write a pattern, set flags, and see matches highlighted live. Capture groups are listed for each match.

0 matches
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Frequently asked

Is this tool free?
Yes. The regex tester is free with no usage limits. Test any JavaScript-compatible regular expression.
Do I need to sign up?
No. Enter a pattern and test string to see matches highlighted live. No account needed.
Is my data private?
All matching runs in your browser inside an isolated Web Worker. Your pattern and test text are never sent to any server.
What happens with slow or dangerous patterns?
The regex executes in a Web Worker with a 1500-millisecond timeout. If the pattern causes catastrophic backtracking (ReDoS), it is automatically stopped before it can freeze your browser.