Which regex flavor does this use?

It uses the JavaScript (ECMAScript) regular-expression engine built into your browser, with support for the g, i, m, s, u and y flags.

Can I see capture groups?

Yes. Each match lists its numbered and named capture groups so you can verify what your pattern is extracting.

No. Matching runs entirely in your browser — your pattern and test string are never sent to a server.

Test and debug regular expressions against sample text with live match highlighting.

Regular expression

/ /g

g global

i ignore case

m multiline

s dotall

u unicode

y sticky

Test string

Highlighted matches 0 matches

Matches will appear here.