Email Regex Tester
Common Patterns
Free Email Regex Validation Tester
Our free email regex validation tester lets developers test and validate email regular expressions against a comprehensive set of valid and invalid sample addresses. Paste your regex pattern, run the test, and instantly see which addresses it matches and which it rejects.
Choosing the right email regex is harder than it looks. A pattern that is too strict will reject valid addresses (like those with plus signs or subdomains). A pattern that is too loose will accept invalid addresses. Our tool tests your pattern against 16 sample addresses — 8 valid and 8 invalid — so you can see exactly how it performs before deploying it in production.
We also provide four pre-built patterns: a simple pattern for most use cases, an RFC 5322 compliant pattern for maximum accuracy, an HTML5 pattern matching browser behaviour, and a strict pattern for conservative validation.
How to Use This Tool
- Enter your regex pattern in the field above (without delimiters).
- Optionally enter a specific email address to test.
- Click Test Pattern.
- Review the results for valid and invalid sample addresses.
- Or click a Common Pattern to load and test a pre-built regex.
Frequently Asked Questions
Which email regex should I use?
For most applications, the simple pattern is sufficient. Use the RFC 5322 pattern if you need maximum standards compliance. The HTML5 pattern matches what browsers use natively for email input validation.
Can regex alone validate an email address?
No. Regex can only validate the format of an email address. It cannot confirm whether the address actually exists or can receive email. Use our email verifier for full validation.
What is the difference between PHP and JavaScript regex?
This tool tests patterns using PHP's preg_match function. JavaScript regex syntax is very similar but has minor differences in some advanced features. Test your pattern in both environments if you need cross-language compatibility.