What is SPF, DKIM, and DMARC?
TL;DR
The three pillars of Email Authentication. SPF (Sender Policy Framework) publishes a DNS record listing servers authorized to send email for your domain. DKIM (DomainKeys Identified Mail) adds a cryptographic signature to emails that recipients can verify. DMARC (Domain-based Message Authentication, Reporting, and Conformance) tells email providers what to do when SPF or DKIM checks fail (quarantine, reject, or take no action) and sends you reports. Together, they prove you're a legitimate sender and protect your brand from spoofing. Implementation requires adding DNS records, your email platform provides the specific values. All three should be configured; many email providers now require them. Check your setup with tools like MXToolbox or Google's Check MX. Proper authentication significantly improves Email Deliverability.
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Frequently Asked Questions About SPF, DKIM, and DMARC
What's the difference between SPF, DKIM, and DMARC?
SPF lists which servers can send your email. DKIM adds a digital signature proving emails weren't tampered with. DMARC tells receivers what to do when SPF/DKIM fail and sends you reports. All three work together.
Do I need all three?
Yes. Each serves a different purpose. SPF alone has limitations DKIM addresses. DMARC ties them together and gives you visibility. Major email providers now require all three for good deliverability.
How do I set up SPF, DKIM, and DMARC?
Your email platform provides the specific DNS records to add. Log into your domain registrar, access DNS settings, add TXT records for each. Most platforms have step-by-step guides. Test after setup to verify.
What happens if I don't set these up?
Emails increasingly land in spam or get rejected entirely. Google and Yahoo require authentication for bulk senders. Without it, you're also vulnerable to spoofing, others can send emails pretending to be you.
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