# What is DMARC? Email authentication and domain alignment

DMARC (Domain-based Message Authentication, Reporting, and Conformance) is an email authentication policy that checks whether a message’s authenticated sending identity aligns with the domain readers see in the From address.

SPF checks whether a sending server is authorized for a domain. DKIM uses a domain’s digital signature to authenticate a message. DMARC adds alignment with the visible From domain: at least one of those mechanisms must both authenticate and align for DMARC to pass.

## Checking a real delivered message

A newsletter arrives with a visible From address at publisher.example. The sender checks the received message’s authentication results to see whether SPF or DKIM passed with a domain aligned to that From domain, then checks the published DMARC policy to understand how failures are handled. A DNS record alone does not prove that this message passed.

## What the published policy changes

A published policy can request monitoring, quarantine or rejection of failing messages, while the receiving system makes its own handling decision. Inspect actual delivered-message results after changing an email provider. A correct DNS record alone does not prove your newsletters authenticate or reach the inbox.

## Check each sending path when results differ

A newsletter and a receipt can look as if they come from the same brand but use separate sending systems. Inspect a delivered message from each. Save the result alongside the system that sent it so the right owner can fix an alignment problem.

## Related terms

[ESP](https://digitalpublishingnews.com/dictionary/esp/)

## Continue reading

[Gmail bulk-sender requirements: check authentication and unsubscribe in a delivered email](https://digitalpublishingnews.com/articles/gmail-bulk-sender-checks/): It checks sender authentication and domain alignment against Gmail’s sender requirements.

## Sources

https://support.google.com/mail/answer/81126?hl=en

https://www.rfc-editor.org/rfc/rfc9989.html

https://support.google.com/mail/answer/81126?hl=en

Editorial method: https://digitalpublishingnews.com/how-we-use-ai/

Canonical: https://digitalpublishingnews.com/dictionary/dmarc/