MX lookup
MX Lookup
Find the mail servers published for a domain and view their numeric priorities in preference order.
Free DNS lookup
Look up a domain
Enter a domain, website URL, or email address. We’ll find and sort its explicit MX records.
What an MX record is
A Mail Exchange (MX) record identifies a host that receives email for a domain and gives it a numeric priority.
When to use this lookup
Use it to confirm whether explicit MX records exist, inspect receiving hostnames, or understand their published routing order.
What MailDNSLab checks
It requests public MX records, validates the normalized response, and sorts mail servers by ascending priority. It also recognizes a valid Null MX record.
Understand MX results
- Priority
- Lower numbers have higher preference. Sending systems can try a higher-numbered server when a preferred one is unavailable.
- Mail server / exchange
- The DNS hostname published to receive mail for the domain. MailDNSLab removes the DNS trailing dot for display.
- Multiple MX records
- Different priorities can support preferred and fallback routing. The same priority can identify equal-priority delivery targets.
- Null MX
- A single
0 .record explicitly states that the domain does not accept email. This is different from simply having no explicit MX record.
Missing records and lookup failures
- MX records found
- One or more explicit receiving hosts were returned and sorted by priority.
- No explicit MX record
- The lookup returned no MX answer. Verify the domain and its DNS configuration; this is not the same as Null MX.
- Null MX
- The domain intentionally publishes that it does not accept inbound email.
- Domain not found
- DNS reports that the domain itself does not exist. Check the spelling before reviewing MX configuration.
- Temporary DNS failure
- A reliable answer was not available. Retry later before drawing a configuration conclusion.
What an MX result does not prove
An MX record does not prove that a server is reachable, that mail will be accepted or delivered, or that the server or domain is secure. It describes public DNS routing information at the time of the lookup.
Common questions
Why are there several MX servers?
Domains can publish preferred and fallback routes or several equal-priority targets. The sending system chooses according to MX and delivery behavior.
What should I do if no MX record is found?
Check the domain spelling and review the domain’s MX configuration with its DNS provider. MailDNSLab reports only explicit MX answers and does not treat absence as a security conclusion.
Why can an MX result change?
DNS records can be updated, cached answers can expire, and temporary DNS conditions can affect a lookup. Retry later when a temporary error is reported.
Does an MX record guarantee that email works?
No. Delivery also depends on server availability, configuration, sender and receiver policy, and other mail-system behavior.
Related Email DNS checks
These tools answer different questions. Use either one when it fits your investigation; neither is a substitute for the current check.