Email DMARC Policy Checker

Check DMARC policy for email authentication, analyze deliverability impact, and get implementation recommendations

DMARC Examples

DMARC Policy Check

Understanding DMARC for Email Delivery

DMARC Policies & Email Impact

none: Monitoring mode - no action taken on failures, only reporting
quarantine: Failed emails are marked as spam or moved to quarantine
reject: Failed emails are rejected outright, strongest protection

Email Delivery Best Practices

  • Start with p=none to monitor without affecting email delivery
  • Gradually move to p=quarantine, then p=reject as you fix issues
  • Set up aggregate reporting (rua=) to track authentication results
  • Test DKIM and SPF alignment before enforcing strict policies
  • Consider subdomain policy (sp=) if subdomains send email

Alignment Modes

Relaxed (r): Allows organizational domain matches (subdomain.example.com matches example.com)
Strict (s): Requires exact domain match for DKIM/SPF alignment

Common Email Delivery Issues

  • Third-party senders may fail if not properly configured in SPF/DKIM
  • Email forwarding can break SPF alignment
  • Mailing lists may modify messages, breaking DKIM signatures
  • Use pct= to gradually roll out enforcement (default 100%)