Regex Tester
Test and debug JavaScript regular expressions with real-time highlighting.
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How to use Regex Tester
Enter your regular expression pattern in the top input.
Add flags (g, i, m, etc.) as needed.
Paste your test string in the text area below.
Matches and groups are highlighted instantly.
Frequently Asked Questions
Which regex flavor is supported?
This tool supports JavaScript Regular Expressions (ECMAScript).
Why is my pattern not matching?
Check if you need global (g) or case-insensitive (i) flags enabled.
Is this secure?
Yes, your patterns and test strings are processed locally.
Why use Kitbase Regex Tester?
Real-time Highlighting
See matches update live as you type your pattern.
JavaScript Regex Engine
Uses your browser's native JS engine for 100% accurate results.
Cheatsheet (Coming Soon)
Quick reference for common regex tokens and patterns.
Match Information
Detailed view of match indices and capturing groups.