Free DMARC Lookup & Validator

What is DMARC?

DMARC (Domain-based Message Authentication, Reporting & Conformance) is a DNS policy record that tells receiving mail servers what to do with emails that fail SPF or DKIM checks. Policies range from p=none (monitor only) to p=quarantine (send to spam) and p=reject (block entirely). DMARC also enables aggregate reporting, so you can see who is sending email on behalf of your domain.

Why does it matter for email deliverability?

Without a DMARC record, anyone can forge your domain in the From address and send phishing emails that appear to come from you. DMARC is the only email standard that actively prevents domain spoofing. Google and Yahoo now require a DMARC record for all bulk senders, and p=reject is becoming the expected baseline for trusted senders.

Common DMARC Issues

• No DMARC record — your domain has no spoofing protection and inbox providers won't trust it
• p=none policy — monitoring only, provides no actual protection against spoofing
• Missing or invalid rua reporting address — you're flying blind with no visibility into failures
• SPF and DKIM alignment failures — DMARC requires at least one to align with the From header domain
• pct= tag below 100% — DMARC policy only applied to a sample of email

How to Fix DMARC Problems

Start by publishing v=DMARC1; p=none; rua=mailto:dmarc-reports@yourdomain.com at _dmarc.yourdomain.com. Monitor the aggregate reports for 2–4 weeks to identify all legitimate email streams. Once you're confident nothing legitimate is failing, move to p=quarantine, then p=reject. Make sure both SPF and DKIM pass and align with the domain in the From header. Services like Postmark, Resend, and Google Workspace have step-by-step guides for their platforms.