Skip to content

Home Topics BIMI and VMC Certification Common Mark Certificates

BIMI and VMC Certification · Common Mark Certificates

Common Mark Certificates (CMC) metrics and benchmarks (2026)

Short answer

For Common Mark Certificates (CMC), track authentication pass rate (target 99%+), spam complaint rate (under 0.1%), hard bounce rate (under 2%), and inbox placement (above 90%) in Google Postmaster Tools, Microsoft SNDS, and seed tests.

It opens BIMI in Gmail to small businesses and new brands that cannot afford or have not completed trademark registration.

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#

  1. Document at least 12 months of logo use (Wayback Machine snapshots, marketing materials).
  2. Prepare the logo as SVG Tiny PS.
  3. Complete organization validation with DigiCert or Entrust.
  4. Publish the certificate URL in the a= tag of your BIMI record.

Frequently asked questions#

Which providers accept CMC?

Gmail accepts CMC as of 2024. Apple accepts VMC and CMC. Yahoo does not require a certificate.

Can I upgrade from CMC to VMC?

Yes, once the trademark registers. Reissue the certificate and update the a= tag.

Keep reading on Common Mark Certificates