Email Address Syntax Validator (RFC 5322)
Local ProcessingVerify syntactic validity of email addresses against RFC 5322 standards locally without sending test emails.
How It Works & Processing Standards
Verify syntactic validity of email addresses against RFC 5322 standards locally without sending test emails.
Tool processing runs in your browser. If you create a calculator or conversion share link, its values are included in the URL. See the privacy policy for account, analytics and advertising data.
Current Limits
- Maximum input length: 100,000 characters
An email address is "local-part@domain", with rules on allowed characters and length. Paste one to check syntax only: a single @, a dotted domain and so on.
Only syntax is checked, not whether the address can receive mail.
What You Can Do
- Syntax check
- Checks the @ count, allowed characters and domain shape.
- No network
- Decided in the browser without DNS or mail-server lookups.
How to Use Email Address Syntax Validator (RFC 5322)
- 1Enter an addressPaste the email address to check.
- 2Read the resultSee whether the format is valid.
Examples
Valid address
Input: hello@example.com
Result: ✓ Valid format
Two @ signs
Input: hello@@example
Result: ✗ Invalid format
Common Use Cases
- Designing or testing sign-up form validation
- Picking out mistyped addresses in a customer list
Frequently Asked Questions (FAQ)
If the format is valid, will mail arrive?
Not necessarily. A missing domain or mailbox still bounces. Sending a confirmation email is the reliable test.