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Free browser-only configuration tool

DMARC Record Generator

Create a monitoring policy first, or review a proposed enforcement policy with clear warnings. Nothing is published or sent to a server.

Build a DMARC draft

Enter a public domain, not a full email address or _dmarc prefix. This tool shows the complete DNS hostname to publish.

Inspect the current DNS first using the Domain Checker. Do not publish a second DMARC TXT policy at the same owner name.

These are domain-owner preferences, not guarantees of delivery, rejection, or inbox placement. Receivers make their own handling decisions.

Use a working mailbox or a report service you control. Up to two email addresses, separated by comma or newline. Do not guess a provider's reporting address. Without rua, you won't receive aggregate reports through this policy.

Private by design: Drafts are composed in your browser. No DMARC input is sent to our Worker, collected, stored, or published.

Publishing a DMARC policy

Create or update one DMARC TXT record at _dmarc.yourdomain.com. Your DNS provider may expect _dmarc as the relative host. Confirm its exact UI before saving, and do not publish a second competing DMARC policy.

Monitoring is not proof that all messages authenticate successfully. Use actual report evidence and message headers to identify overlooked services, verify aligned DKIM or SPF, and consider the effect of forwarding or mailing lists before enforcement.

Limitations and technical sources

The generated value is a draft only. It has not queried public DNS, validated external report authorization, delivered report emails, or proven authentication alignment. Unfamiliar existing tags block rewriting rather than being discarded. Review the DMARC policy standard (RFC 9989), aggregate reporting standard (RFC 9990), and current IANA DMARC tag registry.