DKIM Record Checker
Look up a DKIM public key with its selector. Enter the exact selector when possible. If left blank, Mailthentic tries a finite list of common values and may not find a valid custom selector.
DKIM for
What is a DKIM record?
DKIM adds a cryptographic signature to outgoing email. The public key is published as a DNS TXT record at selector._domainkey.yourdomain.com. A found record confirms that key material is published. Verifying a specific signature also requires the original message.
Finding your selector
Find the exact selector after s= in the DKIM-Signature header or in the sending provider's domain settings. Guessing is unreliable because DKIM does not publish a selector directory.
Keys, rotation, and common errors
The TXT record normally carries public-key data in p=. Domains can publish multiple selectors for different senders or key rotations. A missing result can mean the selector is wrong, the record is at the wrong DNS name, or the change has not propagated.
Follow the DKIM selector guide, then check SPF, DMARC, domain health, and MX routing.
Verify email addresses too
Sign up free and verify individual addresses with full SMTP mailbox confirmation.