MX Lookup
See which mail servers a domain uses, and whether each one works. You also get a verdict on whether the domain is ready to send cold email. Free, no sign-up.
What this checks
- The domain exists in public DNS and publishes MX records.
- It is not a null MX, which says the domain accepts no mail.
- Each MX points at a host name, and that host has an IP address.
- SPF and DMARC too, for the cold email verdict.
Questions
What is an MX record?
It tells other mail servers where to deliver email for a domain. A domain can list several, each with a priority number.
What does MX priority mean?
Senders try the lowest number first. Higher numbers are backups, used when the first server does not answer.
Why do MX records matter for cold email?
Replies need somewhere to land. A domain that cannot receive mail also looks suspicious to receivers, so sending from it hurts delivery.
I changed my MX records. Why do I see the old ones?
DNS answers are cached until their TTL runs out, often for minutes and sometimes for hours. This tool asks public resolvers each time, so try again later.
Do you keep the domains I look up?
No. The lookup runs and the answer comes back to your browser. The domain is not stored.
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