Email · Website glossary

DMARC

Quick answer · What is DMARC?

An email authentication policy and reporting mechanism that relates SPF or DKIM authentication to the visible From domain through alignment.

IN PRACTICE

DMARC: an example

A domain owner first reviews reports to discover legitimate senders before changing enforcement policy.

KEEP IN MIND

A strict policy without a complete sender inventory can disrupt wanted mail; policy changes need monitored testing.

Put the idea to work

Frequently asked questions

What is a practical example of DMARC?

A domain owner first reviews reports to discover legitimate senders before changing enforcement policy.

What should I consider before adopting a strict DMARC policy?

A strict policy without a complete sender inventory can disrupt wanted mail; policy changes need monitored testing.

Which concepts should I read alongside DMARC?

SPF: Sender Policy Framework lets a domain publish which senders are authorized for the envelope-from or HELO identity used in mail transport.
DKIM: DomainKeys Identified Mail attaches a domain-associated cryptographic signature that receiving systems can verify using DNS.