Your browser asks Google Public DNS directly for the domain’s public records. Nothing is sent to this site and nothing is stored; only an anonymous count of checks is kept.
What an MX record is
An MX record tells the world which servers accept email for your domain. The lowest number is tried first; several records give a fallback if the first server does not answer.
What common MX records look like
- Microsoft 365: yourdomain-com.mail.protection.outlook.com, priority 0 (10 on some domains).
- Google Workspace: smtp.google.com, priority 1 (the older aspmx.l.google.com set still exists on many domains).
Common problems
- MX records from two providers mixed after a migration: mail splits between the two.
- An MX that points to an IP address: it must point to a server name that has an A or AAAA address.
- No MX: the domain cannot receive email (unless it is a deliberate null MX).
- A change takes time to spread, depending on the TTL of the old record.
Frequently asked questions
I changed my MX and email is not arriving. Why?
Wait for the TTL of the old record to pass, then check that only one provider is left and that every server resolves.
Does the MX decide where I send email from?
No. MX is for receiving. Sending depends on SPF, DKIM, and DMARC.
My domain has no MX. Is that a problem?
Only if you want to receive email there. The domain can still be spoofed: publish SPF and DMARC.
The other checkers
The tool reads public DNS records only and cannot see your messages. Built in Montreal by Yazan Rajabi.