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Regex Tester

Test JavaScript regular expressions, capture groups, and replacements safely.

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Test string

Email hello@noetrion.com or data@example.org.

Highlighted matches

Replacement

Match details

Run the expression to inspect matches.

Replacement preview

Common example patterns

JavaScript regex cheatsheet

.Any character except line terminators\dDigit\wWord character\sWhitespace^ $Start and end* + ?Repeat or optional(...)Capture group(?:...)Non-capture group

Example patterns are learning aids, not absolute validators. The test runs in a worker and is stopped if it takes too long.