Glossary · Authentication
BIMI lets supporting inboxes show a brand's logo next to its authenticated email, using a DNS record that points to an SVG logo and a mark certificate.
BIMI is a TXT record at default._bimi.yourdomain with two URLs: l= for the logo, a square SVG in the restricted SVG Tiny PS profile, and a= for a mark certificate proving the logo belongs to you.
It only works on top of an enforced DMARC policy: p=quarantine or p=reject, applied to all mail (pct=100, or no pct tag), with no sp=none for subdomains. The point is to decorate mail that is provably yours. Gmail and Apple Mail require a certificate before they show the logo; providers also apply their own reputation bar.
v=BIMI1; l=https://acme.com/brand/logo.svg; a=https://acme.com/brand/vmc.pemEvery domain you run in one inbox, from $3 a mailbox. 14 days free, no card.