Regex Tester Online

Test regular expressions in real-time with match highlighting. Free online regex tester with JavaScript RegExp engine.

PATTERN / / g i m

TEST STRING

RESULT — 0 matches

Results will appear here...

How to Use the Regex Tester

Enter a regular expression pattern, toggle flags (g for global, i for case-insensitive, m for multiline), and type your test string. Matches are highlighted in real time.

Common Patterns

[a-zA-Z0-9._%+-]+@[a-zA-Z0-9.-]+\.[a-zA-Z]{2,} — Email addresses
\b\d{3}[-.]?\d{3}[-.]?\d{4}\b — US phone numbers
^#?([a-fA-F0-9]{6}|[a-fA-F0-9]{3})$ — Hex color codes

FAQ

What regex flavor does this tool use?

JavaScript's built-in RegExp engine (ECMAScript flavor). Supports named groups, lookbehind, and Unicode property escapes.

Is my test data sent to a server?

No. Everything runs in your browser. Nothing is sent anywhere.