Last updated: April 25, 2026
What is BIMI?
BIMI, short for Brand Indicators for Message Identification, is a DNS-based way for a domain owner to publish brand-logo information for authenticated email. It sits after SPF, DKIM, and DMARC. Inbox Insignia treats BIMI as brand readiness for authenticated mail, not as a promise that every inbox will show a logo. BIMI readiness does not guarantee logo display.
The practical goal is simple: once your domain is protected well enough for DMARC enforcement, BIMI lets you check whether participating mailbox providers have the DNS, logo, and evidence signals they can evaluate.
Where BIMI Fits
BIMI depends on the authentication foundation already being in place:
- SPF and DKIM help receiving systems authenticate legitimate mail.
- DMARC ties those checks to the visible From domain and defines policy.
- BIMI publishes brand-logo readiness information for participating receivers after DMARC is enforced.
If DMARC is still set to p=none, or enforcement only applies to part of mail with a low pct value, a BIMI record is not enough. Fix authentication first, then evaluate BIMI.
What BIMI Needs
A first-wave BIMI setup usually includes these pieces:
- A DMARC policy at
p=quarantineorp=reject, typically withpct=100. - A BIMI TXT record, commonly published at
default._bimi.example.com. - An HTTPS URL for an SVG Tiny PS logo file.
- Certificate or evidence material when the target provider requires it, commonly a VMC or CMC PEM URL in the
a=tag.
v=BIMI1;
l=https://brand.example/bimi.svg;
a=https://brand.example/bimi.pemSVG requirements matter. Public provider guidance calls for SVG Tiny PS, absolute dimensions, no scripts, no animation, no external references, and clear title or description metadata. Inbox Insignia checks those basics before treating the logo as usable.
Provider Caveats
BIMI display is provider-dependent. Different mailbox providers evaluate different evidence and policy signals, and the recipient client still matters.
- Gmail requires third-party certification for BIMI, using a Verified Mark Certificate or Common Mark Certificate.
- Yahoo and AOL evaluate a valid SVG, DMARC enforcement, bulk sending, reputation, and engagement. Yahoo says it does not currently require VMCs, but uses them when present.
- Apple Mail depends on the mailbox provider validating BIMI and adding required server-side headers before Apple Mail shows a logo.
That is why Inbox Insignia uses readiness language. The product can tell you whether your domain, record, logo, and evidence are ready for provider evaluation. It cannot force a provider to display a logo.
How Inbox Insignia Helps
The free BIMI checker evaluates the default selector, DMARC enforcement eligibility, record syntax, HTTPS logo URL, SVG Tiny PS basics, certificate evidence, and provider caveats. In the authenticated workflow, BIMI readiness appears alongside advanced domain diagnostics so teams can monitor drift after setup.
Start with the public checker if you only need a point-in-time answer. Use continuous monitoring when your team needs to know if a BIMI record, logo URL, certificate URL, or DMARC policy changes later.
Check BIMI Readiness
Validate the BIMI record, logo, evidence URL, and DMARC prerequisites without treating provider logo display as guaranteed.