intermediateTechnical
DKIM (DomainKeys Identified Mail)
An email authentication method using cryptographic signatures to verify email legitimacy.
By DomainGlossary EditorialLast updated Mar 27, 2026
DKIM is an email authentication method that adds a digital signature to outgoing emails, allowing receiving servers to verify the message was sent by an authorized server and wasn't altered in transit. The DKIM public key is published as a TXT DNS record. DKIM works alongside SPF and DMARC to build a strong email authentication stack, reducing spam and phishing associated with a domain.