Regex Tester
Test and debug regular expressions with live matches, capture groups, and highlighted results.
Regex Tester — Regular expressions are powerful but easy to get wrong. This tester shows you exactly what your pattern matches as you type, highlighting every match in your test text and listing capture groups so you can verify the pattern before you ship it.
Your pattern and test text are processed entirely in your browser and never uploaded.
What is regex tester?
Regular expressions are powerful but easy to get wrong. This tester shows you exactly what your pattern matches as you type, highlighting every match in your test text and listing capture groups so you can verify the pattern before you ship it.
Everything runs locally with the browser’s native regex engine, so patterns and sample data never leave the page — fine for testing against real user data, logs, or anything sensitive.
How to use it
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Type your pattern
For example: \b\w+@\w+\.\w+ to match email addresses.
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Toggle flags
Case-insensitive, multiline, dot-all, Unicode, and sticky modes.
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Enter test text
Every match is highlighted and listed with its capture groups.
Examples
Find email addresses
A simple pattern that finds email-like strings in a block of text.
\b[A-Z0-9._%+-]+@[A-Z0-9.-]+\.[A-Z]{2,}\b Result: All email addresses in the test text, highlighted with capture groups shown.