1

Enter a regex

Type the expression in the “Regular expression” box (no surrounding / needed).

2

Pick flags

Tick g (global), i (ignore case), m (multiline), s (dotall), u (unicode) or y (sticky) as needed.

3

See matches

After entering the test text, results highlight automatically; the list shows position, length and capture groups.

4

Replace

In “Replace Text”, use $1, $2 for groups and $& for the full match; the output updates live.


FAQ

It uses the JavaScript RegExp engine, matching the syntax you use in code.

No. Matching and replacement run locally in your browser; nothing is uploaded.

$1, $2 refer to the 1st and 2nd capture groups; $& means the whole match.