Free Regex Tester Online — Regular Expression Matcher & Debugger Online
Test and debug regular expressions interactively with live highlight preview, capture group breakdown, regex flags (g, i, m, s), and common pattern presets. — 100% free online utility, zero sign-up, zero paywalls, and private client-side processing.
How It Works
Input Pattern
Enter regular expression pattern and toggle flags.
Input Test Text
Paste test string to find matches within.
Inspect Matches
View highlighted matches and captured group parameters.
Frequently Asked Questions
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