Regex · Tester
Test JavaScript regular expressions with live match highlighting, capture groups and flags — all in your browser.
How to test a regex (free)
Type a pattern between the slashes, toggle the flags you need, and paste your text below. Matches are highlighted live and listed with their capture groups. Everything runs locally — nothing is uploaded.
Common regex flags
| g | global — find all matches, not just the first |
| i | case-insensitive |
| m | multiline — ^ and $ match line starts/ends |
| s | dotall — . also matches newlines |
| u | unicode — full code-point matching |
| y | sticky — match from lastIndex only |
Capture groups
Parentheses ( ) create numbered capture groups; (?<name>…) creates a named group. Each match below lists its groups so you can see exactly what the pattern extracts. This is the same ECMAScript engine your JavaScript code uses.
Is my data private?
Yes. Your pattern and test text are evaluated inside your browser tab and never sent anywhere. Because it runs locally, even a slow pattern only affects your own tab — and the tester works offline once loaded.