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Regex Tester
Test regular expressions against text in real time. See highlighted matches and captured groups.
Enter test text to see matches highlighted
Frequently asked questions
What regex flavor does this use?
JavaScript regular expressions (ECMAScript). This matches the behavior of RegExp in modern browsers and Node.js. Features like lookaheads, lookbehinds, and named capture groups are supported.
What do the flags mean?
g = global (find all matches, not just the first). i = case-insensitive. m = multiline (^ and $ match start/end of lines). s = dotall (. matches newlines). u = unicode (treat pattern and text as unicode). y = sticky (match only from the last index).
How do I see captured groups?
Use parentheses in your pattern to create capture groups (e.g., (\d+)-([a-z]+)). The Match Details section shows the values of each group for every match. Hover over highlighted matches to see group values as well.
Test JavaScript regular expressions against any text input. See matches highlighted in real time with detailed capture group information.
Supports all JavaScript regex features including lookaheads, lookbehinds, named groups, and Unicode. Toggle flags individually and see the impact instantly. Perfect for debugging patterns before using them in code.