JavaScript regex tester and explainer
Regex Tester
Build and test JavaScript regular expressions with live highlighting, match details, replacement previews, examples, and a guided syntax explanation.
Developer Tools
Browser based
Runs on the current page
Copy-ready
Use the output where you work
No sign-in
Open the tool and get moving
Developer tool
JavaScript Regex Workbench
Write, test, understand, and replace text with the JavaScript regular expression engine in your browser.
Valid JavaScript regular expression
Matches
2
Capture groups
0
Matched characters
38
Engine
JavaScript
Match 1
dev@entwicklera.com
Characters 8-27, line 1, column 9
Match 2
support@example.com
Characters 31-50, line 1, column 32
Built for the task
Format, validate, encode, decode, and test.
Fast browser utilities for common implementation, debugging, and content-cleanup tasks.
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FAQ
Regex Tester questions.
Which regex engine does this use?
It uses the native JavaScript RegExp engine built into your browser, so results match the behavior available in that browser.
Can I inspect numbered and named capture groups?
Yes. Each match shows its character range, line and column, numbered capture groups, and named capture groups.
Can I test regex replacements?
Yes. The Replace tab previews JavaScript replacement strings using tokens such as $&, $1, and $<name>.
How can I learn what a regex pattern means?
Open Explain & guide to read the current pattern from left to right, copy ready-to-use JavaScript, and consult the built-in syntax reference.
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