DNS / email authentication

DNS, SPF, DKIM and DMARC checker

Inspect the public records that control website resolution and mail authentication. DKIM lookup needs the selector used by your provider.

A / AAAAPublic address records
MX + NSMail and authority routing
SPF / DKIM / DMARCAuthentication records

Enter the apex domain, without a mailbox address.

Examples include default, mail, google or a provider-specific selector.

Enter a domain to see its public DNS and email-authentication records.

How to interpret it

Presence is not the same as correctness.

One SPF record is expected at the sending domain. DMARC is queried at _dmarc.example.com. DKIM public keys are queried at selector._domainkey.example.com.

The checker reports public DNS answers. It cannot prove that a particular message passed alignment; inspect the message's Authentication-Results header for that.

  • Multiple SPF records are an error condition
  • A DKIM selector must match the signer
  • DMARC evaluates alignment with the visible From domain
  • DNS caches can retain old answers until TTL expiry
  • MX presence alone does not prove successful delivery

Need the records corrected?

Send the domain, mail provider and one full message header with sensitive content removed.

Request email DNS review