Free Regex Tester & Debugger Online
Test regular expressions in real-time with match highlighting, group captures, flags, and built-in reference library of common patterns for emails, URLs, and dates. — 100% free online utility, zero sign-up, zero paywalls, and private client-side processing.
How It Works
Enter Regex Pattern
Type your regular expression in the pattern field.
Set Flags
Enable flags: g (global), i (case insensitive), m (multiline), s (dotAll).
Enter Test String
Paste text to test the regex pattern against.
View Matches
See all matches highlighted with group capture contents displayed.
Frequently Asked Questions
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