Test regular expressions with live match highlighting, group capture display, and flag toggles.
What is Regex Tester?
Write and test regex patterns with instant visual feedback. Matches are highlighted in the test string in real-time. See match details including index positions and captured groups. Toggle flags (global, case-insensitive, multiline, dotall) with buttons.
How to Use
Enter your regex pattern
Toggle flags as needed
Type or paste test string
See matches highlighted in real-time
Frequently Asked Questions
Which regex flavor does it use?
JavaScript's native RegExp engine, which is ECMAScript-compatible.
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