DKIM Record
DKIM (DomainKeys Identified Mail) provides cryptographic signature authentication for email messages — proving message integrity and sender authorization — the second foundational email authentication standard alongside SPF.
Why This Matters
DKIM mechanics: sender's mail server cryptographically signs outbound emails using private key; recipient's mail server retrieves public key from sender domain DNS, verifies signature; valid signatures confirm message hasn't been tampered with and sender is authorized. DKIM signature failures trigger spam filter scrutiny similar to SPF failures. DKIM setup required for: marketing automation platforms, transactional email services, and primary domain email infrastructure. Modern email programs require both SPF and DKIM passing for optimal deliverability.
Frequently Asked Questions
Frequently Asked Questions
Why is DKIM needed alongside SPF?
Different protections. SPF authorizes sender IPs; DKIM verifies message integrity and sender authentication. Both needed for comprehensive email authentication. DMARC builds on both for policy enforcement.
What happens when DKIM fails?
Spam filter scrutiny similar to SPF failures. Combined SPF + DKIM passage required for optimal deliverability at major ESPs (Gmail, Outlook). Either failing increases spam folder placement probability.