Regular Expression (Regex) Tester & Debugger
Free in-browser Regular Expression (RegExp) testing suite. Features live character match highlighting, detailed capture groups breakdown, flag configuration (g, i, m, s), string substitution preview, built-in common pattern presets (Email, IP, URL, Date, Hex), and a quick regex cheat sheet. 100% client-side privacy.
Loading Regex engine...
How to Test Regular Expressions in 3 Steps
Enter Regex Pattern
Type your regular expression pattern and toggle flags (Global, Case-Insensitive, Multiline).
Input Test String
Paste your target text or select a preset pattern from the toolbar.
Inspect Matches & Groups
View live highlighted matches, check capture group indices, or test string replacement.
Frequently Asked Questions
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