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MX record lookup
See which mail servers receive email for a domain, in priority order, and whether each one actually resolves.
Receive email on a subdomain with Groundmail
Point an MX record at Groundmail and mail to that domain arrives as a webhook and through the API you send with. Good for replies, support inboxes and parsing.
Reading MX records
Senders try the lowest priority number first and fall back to the next. Every MX host needs its own A or AAAA record; an MX that points at a CNAME or an IP address breaks delivery at some senders.
A single MX of priority 0 pointing at "." is a null MX: the domain says it accepts no mail at all.
Questions
What is an MX record?
A DNS record that names the server that receives email for a domain. A domain can have several, with priorities that set the order senders try them in.
Do I need MX records to send email?
Not to send, but receivers check that your From and return-path domains can receive mail, and replies and bounces need somewhere to go. A sending domain with no MX looks less trustworthy.
Can an MX record point to a CNAME?
It shouldn't. RFC 2181 says MX targets must have their own address records, and some mail servers refuse to follow a CNAME.