Regex Tester

Online Regular Expression Tester

Test your regular expressions in real time. Enter a regex pattern and a test string to see all matches highlighted instantly. Supports JavaScript regex syntax with flags.

How to Use

Type your regular expression between the slashes. Add flags (g, i, m, s) after the closing slash. Paste or type your test string below. Matches are highlighted automatically as you type.

Common Regex Flags

• g — Global: find all matches, not just the first
• i — Case-insensitive matching
• m — Multiline: ^ and $ match line boundaries
• s — Dotall: . matches newlines too

Quick Reference

• . — Any character (except newline)
• \d — Digit [0-9]
• \w — Word character [a-zA-Z0-9_]
• \s — Whitespace
• * — Zero or more
• + — One or more
• ? — Zero or one
• {n,m} — Between n and m times
• () — Capture group
• | — Alternation (OR)
• ^ / $ — Start / End of string

Frequently Asked Questions

Which regex flavor does this use?

This tool uses JavaScript's native RegExp engine, which is ECMAScript-compliant. Most common regex syntax is supported.

Is my data safe?

Yes. All matching runs entirely in your browser. Nothing is sent to any server.