About Regular Expression (Regex) Tester
Interactive regex testing tool with flag toggles (g, i, m, s, u), match indices, capture group extraction, error diagnostics, and ready-to-use common pattern presets.
Key Capabilities & Features
- Real-time matching against test strings
- Interactive flag toggles (global, multiline, ignoreCase, dotAll, unicode)
- Presets for Emails, URLs, IPs, Phone Numbers, Passwords
- Match index tracking and group extraction
- Syntax error detection
How to Use Regular Expression (Regex) Tester
1
Enter Regex Pattern
Type your regular expression pattern and toggle desired flags.
2
Paste Test String
Enter the text you want to evaluate against your pattern.
3
Inspect Matches
Review all captured matches, indices, and validation states in real-time.
Privacy & In-Browser Execution Guarantee
Regex parsing is performed locally in your browser engine with complete confidentiality.
Frequently Asked Questions
Which regex dialect does this tool support?
This tool uses the standard JavaScript (ECMAScript) RegExp engine natively supported across all modern web browsers.
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