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DMARC Record Generator

Generate a properly formatted DMARC TXT DNS record for your domain with a guided form.

% of messages policy applies to. 100 = all.
Generated DMARC record
v=DMARC1; p=none;
DNS record name: _dmarc.yourdomain.com — Type: TXT

About DMARC Record Generation

DMARC (Domain-based Message Authentication, Reporting & Conformance) is an email authentication policy published as a TXT DNS record at _dmarc.yourdomain.com. It tells receiving mail servers what to do with messages that fail SPF or DKIM authentication, and where to send reports about those failures.

Recommended deployment path

  1. Start with p=none — Monitor-only mode. Collect aggregate reports to understand your email sending ecosystem before enforcing any policy. Run this for at least 2–4 weeks.
  2. Move to p=quarantine — Failing messages are sent to spam/junk. Set pct=25 initially and gradually increase to 100 as you confirm legitimate sources are passing.
  3. Enforce p=reject — The goal state. Failing messages are rejected outright. This provides the strongest protection against domain spoofing and phishing using your domain name.

DMARC alignment

DMARC requires "alignment" between the domain in the From: header and the domain validated by SPF or DKIM. Relaxed alignment (adkim=r / aspf=r) allows subdomain matches; strict alignment (s) requires an exact match. Most organisations use relaxed alignment to support legitimate subdomains.

Aggregate reports (rua)

Set the rua tag to an email address where ISPs will send daily XML reports. These reports show which IP addresses are sending email claiming to be from your domain, and whether SPF and DKIM are passing. DMARC report parsing tools (like the DMARC Report Parser on this site) help make sense of the XML data.

Related tools

All Email & Deliverability →
Email Header Analyzer Paste raw email headers and get a full breakdown of routing, authentication and … SPF Record Generator Build a valid SPF TXT record for your domain using a simple guided form. DKIM Helper Understand DKIM setup, generate DKIM key pairs and get guidance for your DNS rec… MX Health Summary Run a full email health check — MX, SPF, DMARC, DKIM and blacklist status in one…

Frequently asked questions

Where do I add the DMARC record?
Add it as a TXT record at _dmarc.yourdomain.com (not yourdomain.com). For example, for example.com, create a TXT record at _dmarc.example.com.
What policy should I start with?
Start with p=none to monitor without affecting delivery. Review your aggregate reports (rua). Once confident in your SPF/DKIM setup, move to p=quarantine then p=reject.