DMARC explained: A complete guide
January 15, 2024
DMARC (Domain-based Message Authentication, Reporting, and Conformance) is a critical email security protocol that prevents email spoofing and phishing attacks.
What is DMARC?
DMARC builds on two existing authentication mechanisms: SPF (Sender Policy Framework) and DKIM (DomainKeys Identified Mail). It tells receiving mail servers what to do when an email fails authentication checks.
Why DMARC matters
- Prevents spoofing: Stops attackers from sending emails that appear to come from your domain
- Improves deliverability: Major email providers (Gmail, Outlook) require DMARC for bulk senders
- Provides visibility: Reports show who's sending email on your behalf
- Protects reputation: Prevents your domain from being used in phishing attacks
DMARC policies
DMARC has three policy levels:
- p=none: Monitor only (no enforcement)
- p=quarantine: Send suspicious emails to spam
- p=reject: Block suspicious emails entirely
Getting started
Run a free audit to check your current DMARC configuration and get specific recommendations for your domain.