Regex tester
Test regular expressions against sample text with live matches.
match(es)
This regex tester lets you write a regular expression and immediately see what it matches against your own sample text. As you type the pattern and toggle flags like global, case-insensitive, or multiline, matches are counted and captured groups are listed so you can confirm the expression behaves the way you expect. It is built for debugging patterns before you commit them to code, saving you the round trips of editing and rerunning a script. Matching runs entirely in your browser using the standard JavaScript regex engine.
Frequently asked questions
Which regex flavor does this use?
It uses the JavaScript regular expression engine, so syntax matches what you would write in browser or Node.js code.
What do capture groups show?
Each parenthesized group in your pattern is listed alongside the text it captured, including named groups, which makes complex patterns easier to verify.
Why is my pattern matching too much or too little?
Greedy quantifiers grab as much as possible by default. Adding a question mark makes them lazy, and anchoring with ^ or $ can tighten the match.
What do the global and multiline flags do?
The global (g) flag finds every match instead of stopping at the first, while multiline (m) makes ^ and $ match at each line break rather than only the start and end of the whole string.
Will a pattern that works here work in another language?
Mostly, but not always. This uses the JavaScript engine; flavors like PCRE, Python, or Go differ on lookbehind, named-group syntax, and some escapes. Test in your target environment for anything advanced.
How do I match a literal special character?
Escape it with a backslash — \. matches a literal dot, \( a literal parenthesis. Without the backslash, those characters carry their special regex meaning.
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