Reports are the only way to see who is sending as your domain, including vendors you forgot and attackers you never knew about. Moving to p=reject safely depends on reading them.
The metrics that matter#
- Authentication pass rate: share of mail passing SPF, DKIM, and DMARC alignment. Healthy: 99% or higher.
- Spam complaint rate: Gmail enforces at 0.3%; stay under 0.1%.
- Hard bounce rate: under 2%; above 5% triggers platform reviews.
- Inbox placement: above 90% across major providers via seed tests.
- Engagement: click and reply rates by segment; opens are unreliable after Mail Privacy Protection.
Where to read them#
- Google Postmaster Tools for Gmail domain reputation, spam rate, and authentication.
- Microsoft SNDS and JMRP for Outlook.com IP reputation and complaints.
- Your ESP's delivery and bounce reports.
- DMARC aggregate reports for authentication by source.
Improving the numbers#
- Publish rua=mailto: pointing to a dedicated mailbox or a report processor.
- Collect reports for at least two weeks before drawing conclusions.
- Group sources by IP owner and match each to a known vendor.
- Fix alignment for legitimate sources; treat unknown high-volume sources as spoofing.
- Track pass rate weekly and tighten policy as it approaches 100%.
<record>
<row><source_ip>203.0.113.10</source_ip><count>412</count>
<policy_evaluated><disposition>none</disposition><dkim>pass</dkim><spf>fail</spf></policy_evaluated></row>
<identifiers><header_from>example.com</header_from></identifiers>
</record>Frequently asked questions#
How do I read a DMARC report?
Each record lists a source IP, message count, SPF and DKIM results, and alignment. Use an analyzer to aggregate by source; the goal is to name every IP range.
Why do I see mail from IPs I do not recognize?
Common causes are forwarding, a vendor you forgot, an employee's personal tool, or spoofing. Volume and geography usually tell them apart.