SPF, DKIM & DMARC Explained
SPF, DKIM, and DMARC are email authentication protocols that verify you're who you say you are. They're essential for deliverability—without them, your emails are more likely to land in spam.
SPF (Sender Policy Framework)
SPF specifies which mail servers are authorized to send email on behalf of your domain. It's a DNS TXT record that lists approved sending IPs.
DKIM (DomainKeys Identified Mail)
DKIM adds a digital signature to your emails, proving the message wasn't altered in transit. It uses public-key cryptography.
DMARC (Domain-based Message Authentication)
DMARC tells receiving servers what to do if SPF or DKIM checks fail. It also enables reporting so you can monitor authentication issues.
Why All Three Matter
Email providers like Google and Microsoft now require proper authentication. Without it:
Emails may be rejected outright
Messages land in spam more often
Your domain reputation suffers
Frequently Asked Questions
Do I need all three?
Yes. SPF and DKIM are foundational; DMARC ties them together and adds protection against spoofing.
How long do changes take to propagate?
DNS changes typically propagate within 24-48 hours, though some providers may take longer.