X-RAY // MAIL // MX

MAIL SERVERS (MX)
CHECK.

List the MX records of a domain, check that each server resolves, identify the provider (Google, Microsoft 365, Zoho…) and spot a null MX.

Runs only this check. For all 33 checks at once, use the full Domain X-Ray. Public lookups only; nothing is stored on the server.

Mail servers (MX)

WAITING

Enter a domain above to run this check.

01 // WHAT THE CHECK VERIFIES

Lists the MX records, which say which servers receive the domain email, checks that each one resolves and identifies the provider.

02 // WHY IT MATTERS

Without MX the domain receives no email. A null MX (0 .) is the correct way to declare that the domain receives no mail.

03 // HOW TO READ THE RESULT

OK: There is an MX and the servers resolve; the provider shows when it is known. An MX that points to a CNAME is flagged.
FAIL: An MX server does not resolve: messages to it are rejected or stay queued at the sender.
INFO: No MX (the domain receives no email) or a null MX (0 .), which is the correct way to declare that.

ERROR and TIMEOUT mean the query did not finish (the source was down or slow), not a problem with the domain: run the check again.

04 // HOW TO FIX

The MX points to a name with an A or AAAA, never to an IP or a CNAME. If the domain receives no email, publish the null MX of RFC 7505:

example.com. MX 0 .

Would rather have someone else do it? Bit Happens can fix this →

05 // CONTINUE