DMARC Guide

Learn how to set up DMARC for your domain and monitor it with DMARC Monitor.

What is DMARC?

DMARC (Domain-based Message Authentication, Reporting, and Conformance) is an email authentication protocol that builds on SPF and DKIM. It tells receiving mail servers what to do when emails fail authentication and provides you with reports about who is sending email on behalf of your domain.

Why You Need DMARC

  • Prevent email spoofing: Stop attackers from sending phishing emails that appear to come from your domain
  • Protect your brand: Ensure only authorized servers send email as your domain
  • Gain visibility: Receive reports showing all email sources using your domain
  • Improve deliverability: Authenticated emails are more likely to reach inboxes

Setting Up DMARC with DMARC Monitor

Step 1: Add Your Domain

Sign up for DMARC Monitor and add your domain from the Domains page. We'll automatically scan your existing DNS records to check your current email authentication setup.

Step 2: Add the DMARC Record

After adding your domain, we provide you with the exact DMARC DNS record to add. You'll get a TXT record with the host _dmarc and a value that includes your unique reporting address.

Add this record to your domain's DNS settings through your domain provider (Cloudflare, GoDaddy, Namecheap, etc.).

Step 3: Start Receiving Reports

Once your DMARC record is live, email providers like Google, Microsoft, and Yahoo will start sending aggregate reports to DMARC Monitor. Reports typically arrive within 24-48 hours.

Step 4: Analyze and Improve

Use your DMARC Monitor dashboard to see all email sources, identify unauthorized senders, and gradually tighten your policy from p=none to p=quarantine and eventually p=reject.

DMARC Policy Levels

p=none (Monitor)

No action taken on failing emails. Use this first to collect data and identify legitimate email sources.

p=quarantine

Failing emails go to spam/junk folder. Use once you've verified all legitimate sources pass authentication.

p=reject

Failing emails are blocked entirely. Maximum protection once you're confident in your email authentication.

DMARC Record Tags Explained

TagDescriptionExample
vVersion (required)v=DMARC1
pPolicy (required)p=none
ruaAggregate report addressrua=mailto:reports@example.com
rufForensic report addressruf=mailto:forensic@example.com
pctPercentage of emails to apply policypct=100
spSubdomain policysp=reject

Beyond DMARC: Complete Domain Protection

DMARC is just the foundation. DMARC Monitor provides comprehensive tools to ensure your domain's email infrastructure is fully protected and compliant.

Domain Health Score

Get an instant overview of your domain's email security posture. Your health score combines DMARC policy strength, SPF validity, DKIM configuration, and other factors into a single metric that helps you track improvements over time.

  • Real-time scoring based on DNS configuration
  • Track progress as you strengthen your DMARC policy
  • Identify weak points in your email authentication

RBL (Blacklist) Monitoring

Even with perfect DMARC, your emails won't reach inboxes if your sending IPs are blacklisted. DMARC Monitor checks your domain and mail server IPs against major Real-time Blackhole Lists (RBLs).

  • Monitor against 50+ blacklists including Spamhaus, Barracuda, SORBS
  • Get alerts when your IPs appear on a blacklist
  • Identify which sending sources may be causing reputation issues

DNS & SSL Certificate Monitoring

Your email authentication depends on DNS records being correctly configured. DMARC Monitor continuously monitors your critical DNS records and SSL certificates to catch issues before they affect email delivery.

  • Monitor DMARC, SPF, DKIM, MX, and MTA-STS records
  • SSL certificate expiration alerts
  • Get notified of unexpected DNS changes

Compliance Reporting

Generate reports showing your domain's DMARC compliance status over time. Perfect for security audits, management reporting, or demonstrating compliance with email security requirements.

  • Track DMARC pass/fail rates over time
  • Export compliance data for audits
  • Monitor progress toward p=reject enforcement