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Regex Tester
Test JavaScript regular expressions live, see all matches highlighted, and check capture groups.
Warning: avoid catastrophic patterns with nested quantifiers (for example
(a+)+). They can hang your browser. Test on small text first.0 match(es)
How to use
- Type a pattern and flags.
- Paste test text.
- Matches are highlighted instantly.
Frequently asked questions
Why the warning about catastrophic patterns?
Patterns with nested quantifiers can hang the browser, so keep patterns simple and test on small text first.
Which flavour is this?
JavaScript RegExp, the same engine used in browsers and Node.js.
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