whohostsitCheck DKIM
and BIMI.
Find a domain’s DKIM keys, check their strength, and see whether
it’s ready for a BIMI brand logo in the inbox.
Keys, strength, and brand logo.
DKIM keys found, their size and status, and the BIMI record appear here.
PUBLIC DATA. ONE SIMPLE LOOKUP.How DKIM and BIMI work
DKIM signs each email with a private key. The matching public key is published in DNS at selector._domainkey.yourdomain, where the selector is a name chosen by your mail provider, such as selector1 for Microsoft 365 or google for Google Workspace.
BIMI builds on DMARC: once your domain enforces p=quarantine or p=reject, a BIMI record at default._bimi points to an SVG logo that supporting inboxes show next to your messages. Some, including Gmail, also require a verified mark certificate.
Common questions
How do I find my DKIM selector?
Open an email sent from your domain, view the original message or its headers, and find the DKIM-Signature line. The s= value is the selector and d= is the domain.
What DKIM key length should I use?
2048-bit RSA is the current standard. 1024-bit keys are considered weak, and anything shorter is insecure and ignored by many receivers.
Why does it say no DKIM key was found?
We can only try common selectors, because DNS can’t list a domain’s selectors. Many providers use unique or rotating names; enter the selector from your email headers to check it.