MX record lookup
See which mail servers receive mail for a domain, in priority order, straight from its authoritative nameservers.
Part of the DNS lookup.
Comparing all 13 public resolvers takes a few seconds.
What this checks
MX records name the servers that accept email for a domain. Each has a priority: senders try the lowest number first and fall back to higher ones if it does not answer. Equal numbers share the load.
The lookup asks the domain's own authoritative nameservers, so you see the records as they are published right now rather than an answer cached by a resolver. You can switch to a public resolver in the form, or compare 13 of them at once with the DNS propagation check after a change.
Some typical results:
| MX target | Mail is handled by |
|---|---|
smtp.google.com, or aspmx.l.google.com and its alternates |
Google Workspace |
*.mail.protection.outlook.com |
Microsoft 365 |
0 . |
Nobody: a null MX (RFC 7505) says the domain accepts no mail |
Common problems and fixes
No MX records. Senders then fall back to the domain's A record, which usually is a web server that does not accept mail. Add the records your mail provider gives you. If the domain should never receive mail, publish a null MX: example.com. MX 0 .
The MX points at an IP address or a CNAME. An MX target must be a host name with its own A or AAAA record, not an address or an alias (RFC 2181, RFC 5321). Some senders accept it anyway; many do not.
Old records left behind after a move. Senders may still deliver to the old provider. Remove every MX that does not belong to the new one.
Mail arrives but goes to spam. That is not an MX problem. Run the email security check for SPF, DKIM and DMARC, and work through Why is my email going to spam?.
For the other record types (A, TXT, CAA and more) use the full DNS lookup.