Regex Tester & Cheat Sheet

Test regular expressions in real-time. Matches are highlighted as you type.

How to Use the Regex Tester

Enter your regular expression pattern in the pattern field and your test text in the input area. Matches are highlighted instantly as you type. The built-in cheat sheet provides quick reference for common regex patterns, character classes, quantifiers, and anchors.

Frequently Asked Questions

Which regex flavor is supported?

The tool uses JavaScript RegExp engine, which is compatible with most modern regex features including lookaheads, lookbehinds, and named groups.

Can I save my regex patterns?

Patterns are remembered in your browser session. Bookmark the page with your pattern in the URL hash to save it permanently.