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Test and debug regular expression patterns for email validation. Verify your pattern matches valid emails and rejects invalid formats.
> Test patterns against real text and inspect all matches.
> Toggle flags, debug errors, and copy the final expression.
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A practical pattern for most applications: /^[a-zA-Z0-9._%+-]+@[a-zA-Z0-9.-]+\.[a-zA-Z]{2,}$/. This matches standard emails like user@example.com while rejecting obvious mistakes. Use our tester to paste your own pattern and instantly see which strings match and which fail, making it easy to refine your validation logic without deploying code.
/^[a-zA-Z0-9._%+-]+@[a-zA-Z0-9.-]+\.[a-zA-Z]{2,}$/ balances strictness and practicality. Fully RFC 5321-compliant regexes are extremely complex and rarely necessary for form validation.
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