What is Email Validation?

Email validation checks whether an email address conforms to RFC 5322 standards and performs additional checks like domain validation and common typo detection. It ensures addresses are properly formatted and potentially deliverable.

How This Tool Works

1. Enter an email address to validate
2. The tool performs multiple validation checks:
   • Format validation (RFC 5322 compliance)
   • Local part length (max 64 characters)
   • Domain length (max 253 characters)
   • MX record lookup (domain can receive email)
   • Common typo detection for popular domains
3. Results show pass/fail for each check
4. Overall validity determination

Email Address Structure

A valid email address has two parts separated by @:

• Local Part: user (before @) - max 64 characters
• Domain: example.com (after @) - max 253 characters

RFC 5322 Validation Rules

According to RFC 5322, valid email addresses must:

• Have exactly one @ symbol separating local and domain parts
• Local part can contain: letters, numbers, and special characters (. _ % + -)
• Local part cannot start or end with a dot
• Local part cannot have consecutive dots
• Domain must be valid hostname with at least one dot
• Domain must have valid TLD (top-level domain)
• Total length should not exceed 320 characters

What This Tool Checks

• Format Validation: Checks against regex pattern for RFC 5322
• Length Validation: Verifies local part (≤64) and domain (≤253) lengths
• MX Records: Confirms domain has mail servers configured
• Typo Detection: Suggests corrections for common mistakes (gmial.com → gmail.com)

Common Email Typos

Validation Limitations

This tool cannot verify:

• Whether the email address actually exists
• Whether the mailbox is active and accepting mail
• Whether the address belongs to a real person
• Whether the address is a spam trap

For these checks, you would need to send an actual email or use specialized verification services.

Best Practices for Email Validation

• Validate format before attempting to send email
• Check MX records to ensure domain can receive mail
• Use double opt-in for subscriptions to verify ownership
• Implement typo detection to improve user experience
• Don't be too strict - some valid addresses may look unusual
• Regular expression alone is not enough - use multiple checks
• Clean email lists regularly to remove invalid addresses

Use Cases

• Form Validation: Check emails during user registration
• List Cleaning: Validate existing email lists
• Data Quality: Ensure database integrity
• Prevent Typos: Catch common mistakes before sending
• Deliverability: Remove invalid addresses to improve sender reputation

Advanced Validation Example

Integration Tips

• Validate on both client-side (immediate feedback) and server-side (security)
• Show helpful error messages to guide users
• Suggest corrections for detected typos
• Consider implementing real-time validation as users type
• Log validation failures to identify common issues

Related Tools

• MX Checker - Verify mail server configuration
• Email Deliverability Tester - Test domain email setup
• DNS Record Viewer - View domain DNS records
• SPF Record Generator - Configure email authentication
• Slug Generator - Create URL-safe strings from email addresses