---
title: "What is DMARC?"
url: "https://lookvalid.com/glossary/dmarc.md"
canonical_url: "https://lookvalid.com/glossary/dmarc"
last_updated: "2026-10-18"
type: "conceptual"
summary: "DMARC is a DNS policy that tells receivers what to do with mail that fails SPF and DKIM checks tied to the visible \"From\" domain, and where to send reports."
related: ["https://lookvalid.com/glossary/spf.md", "https://lookvalid.com/glossary/dkim.md", "https://lookvalid.com/glossary/mx-record.md", "https://lookvalid.com/products/email-domain-check.md"]
---

# What is DMARC?

DMARC is a DNS policy that tells receivers what to do with mail that fails SPF and DKIM checks tied to the visible "From" domain, and where to send reports.

The policy is "none" (only report), "quarantine" (treat as suspicious) or "reject" (refuse). The record sits at the _dmarc name of the domain and can ask receivers for summary reports.

A domain with a strict DMARC policy is harder to impersonate. A missing policy is common on old or small domains and is a mild signal on its own.

## Related

- [What is SPF (Sender Policy Framework)?](https://lookvalid.com/glossary/spf.md)
- [What is DKIM (DomainKeys Identified Mail)?](https://lookvalid.com/glossary/dkim.md)
- [What is MX record (Mail Exchanger record)?](https://lookvalid.com/glossary/mx-record.md)
- [Email Domain Check API](https://lookvalid.com/products/email-domain-check.md)