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Regex Tester
Test and debug regular expressions with live matching and highlighting. See captured groups, match indices, and toggle flags in real time. All processing happens in your browser.
no account
no rate limit
nothing stored
Input
/
/
Output
Highlighted Matches
matches
Match Details
Match
index
Group :
// how it works
How it works
step 01
Write
Enter your regular expression pattern and toggle flags like global, case insensitive, and multiline.
step 02
Test
Enter test text and see matches highlighted live. View captured groups and match positions.
step 03
Copy
Copy the regex pattern with flags and use it in your code. Uses JavaScript regex syntax.
// frequently asked
Common questions
Which regex flavor does this use?
JavaScript's native RegExp syntax, the same engine that runs in every modern browser and in Node.js.
Is my test string sent anywhere?
No. Matching happens entirely in your browser using the built-in RegExp engine.
Why does my pattern behave differently in PHP or Python?
Each language ships its own regex engine with small differences in syntax and lookaround support. Test the final pattern in the language you will actually use it in.
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