Regex Tester

Test regular expressions with live feedback and real-time matching on input strings. This comprehensive regex tool highlights matches, extracts groups, supports multiple flags including global and case-insensitive options, and includes a library of common patterns. Perfect for developers working on data validation, text processing, form validation, and learning regular expression syntax through practical, interactive testing and experimentation.

Live Matching Group Extraction Multiple Flags Pattern Library

Quick Examples

EMAIL: Email pattern match
PHONE: Phone number validation
FLAGS: g, i, m supported

Regular Expression (e.g. /\d+/g)

Test String

Matches

No matches yet.

Help & Related Tools

Everything you need to know

FAQ Frequently Asked Questions

What regex flags are supported?

The tool supports common flags including global (g) for all matches, case-insensitive (i), multiline (m) for ^ and $ anchors, and sometimes others like single-line (s) and unicode (u) depending on browser support.

Can I test regex for different programming languages?

The tool uses JavaScript regex engine, which is similar to most modern languages but may have slight differences. For language-specific features, always test in your target environment, but the tool covers most common regex patterns.

How do I see capture groups in my matches?

The tool highlights matches and shows capture group contents separately. Parentheses in your regex create numbered groups (1, 2, 3...) and named groups that you can see in the results panel with their captured values.

Why is my regex not matching what I expect?

Common issues include forgetting to escape special characters (. * + ? ^ $ | [ ] ( )), incorrect quantifiers, or case sensitivity. Use the real-time feedback to debug by testing simpler patterns first, then building complexity.

Are there preset patterns for common use cases?

Yes, the tool includes a library of common regex patterns for emails, URLs, phone numbers, dates, and other frequent validation needs. These serve as starting points that you can modify for your specific requirements.