Free regex tester with live highlighting. Test regular expressions against your text in real time, with a library of common patterns and a replace mode.
Type your regular expression pattern in the pattern field. Toggle flags like global (g), case-insensitive (i), or multiline (m) as needed.
Paste or type the text you want to test against in the test string area.
Matches are highlighted in real-time. See match count, positions, and captured groups below.
This tool uses JavaScript's built-in RegExp engine, which supports standard regex syntax including lookahead, lookbehind, named groups, and Unicode properties.
g (global) finds all matches, i (case-insensitive) ignores case, m (multiline) makes ^ and $ match line boundaries, s (dotAll) makes . match newlines.
Yes. Use parentheses () for capture groups and (?<name>) for named groups. Matched groups are displayed in the results.
Yes. Everything runs in your browser. No regex patterns or test strings are sent to any server.
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