Test a regular expression
Write a pattern and see every match highlighted live against your own sample text, with capture groups listed for each one.
Enter a regular expression and toggle case-insensitive, multiline, or dot-all as needed.
Matches are highlighted live as you type, in either box.
Every match lists its index and any capture groups, numbered and named.
Frequently asked
Is my text sent anywhere?
No. Matching runs using your browser's own regular expression engine, in this tab. Nothing is sent anywhere.
Which regex flavor does this use?
JavaScript's native RegExp. The same engine behind every regex you'd write in a browser or in Node.js.
Why is the global flag always on?
It's applied automatically so every match in your text is found, not just the first one. You don't need to add it yourself.
Is there a limit on matches?
Matching stops at 1,000 to keep the page responsive against a pattern that matches almost everything.
Does this work offline?
Yes, once the page has loaded.