Real-time Matching
As you type a pattern or test string, matches are highlighted instantly. The match count, capture group count, and execution time update in real time — giving you immediate feedback without clicking a button.
Test regular expressions in real time. See matches highlighted instantly with capture group details and execution time.
. any char
\d digit
\w word char
\s whitespace
\b word boundary
^ start
$ end
* 0+
+ 1+
? 0 or 1
{n,m} n to m
[abc] char class
[^abc] negated
(…) capture group
(?:…) non-capture
(?=…) lookahead
(?<=…) lookbehind
a|b alternation
\x41 hex char
\n newline
As you type a pattern or test string, matches are highlighted instantly. The match count, capture group count, and execution time update in real time — giving you immediate feedback without clicking a button.
Use standard JavaScript regex flags: g (global), i (case-insensitive), m (multiline), s (dotAll), u (unicode), y (sticky). Capture groups are shown in the match details table with their index positions.
It uses your browser's built-in JavaScript RegExp engine, which follows the ECMAScript specification. Syntax like lookbehind (?<=…) works in modern browsers.
To prevent browser freezing, matching stops after 5,000 results and the details table shows up to 200 entries. This is more than enough for most use cases.
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