Pro move: type dmarc:yourdomain.com or blacklist:1.2.3.4 straight into the box — it switches tools for you.
About this tool. DMARC tells receiving servers what to do with mail that fails SPF and DKIM — and sends you reports about who's sending as your domain. This check decodes every tag of your policy in plain English and flags the settings that leave you exposed.
How to read your dmarc record checker results
DMARC is a TXT record at _dmarc.yourdomain that tells receivers what to do with mail that fails SPF and DKIM. We decode every tag.
The policy (p=) is the key: none only monitors, quarantine sends failures to spam, and reject blocks them outright.
The rua= address is where aggregate reports are sent. Without it you are flying blind on who is sending as your domain.
Common problems and how to fix them
You have p=none and want protection
Move to p=quarantine, then p=reject, once your reports confirm all legitimate mail passes. Rushing to reject can block real mail.
No DMARC reports arriving
Add a rua= mailto address. Make sure that mailbox can receive from external domains.
Common questions.What is a DMARC record?
A DNS TXT record that sets a policy for mail failing SPF and DKIM, and requests reports so you can see who sends as your domain.
What does p=none mean?
Monitoring only. It takes no action on failing mail, and is the safe first step while you gather reports.
What is DMARC alignment?
For DMARC to pass, the domain in the From header must line up with the domain validated by SPF or DKIM. Alignment is what stops spoofing.