A verified logo increases open rates and trust, and the DMARC prerequisite forces a domain to finish its authentication work. It is also a visible signal that a message is not a phish.
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#
- Reach DMARC p=quarantine (pct=100) or p=reject on the sending domain.
- Produce your logo as an SVG Tiny 1.2 Portable/Secure file, square, centered, with a solid background.
- Obtain a VMC or CMC from an approved certificate authority if you want display in Gmail and Apple Mail.
- Publish default._bimi.yourdomain.com with l= (logo URL) and a= (certificate URL).
- Validate with a BIMI inspector and send a test to Gmail, Yahoo, and Apple seed accounts.
default._bimi.example.com. IN TXT "v=BIMI1; l=https://example.com/brand/logo.svg; a=https://example.com/brand/vmc.pem"Frequently asked questions#
Does BIMI work without a VMC?
Yahoo and Fastmail display BIMI logos with DMARC enforcement alone. Gmail and Apple require a VMC or CMC.
What image format does BIMI require?
SVG Tiny 1.2 Portable/Secure. No PNG, JPG, or standard SVG.
Does BIMI improve deliverability?
Not directly. Its prerequisite, DMARC enforcement, does. The logo mainly lifts engagement and trust.