Network Tools

MX Lookup

Check mail exchanger records for a domain.

Input

Runs as you type · to force a run

Result

Fill in the form — the answer appears here.

How to use the MX Lookup

Use this lookup to see where a domain directs inbound email and whether it publishes explicit, implicit, or Null MX behavior.

  1. Enter the domain after the @ in an email address, not the hostname of a mail server.
  2. Read explicit exchangers from lowest priority number to highest; senders normally try lower numbers first.
  3. Resolve every exchanger and compare the hostnames and priorities with the mail provider's current setup instructions.

How to read the result

Explicit records name the receiving mail servers. An implicit result means no MX record exists but the domain has an address. A record with priority 0 and exchange . is a Null MX declaration that the domain does not accept email.

Example

Input
example.com
What to look for
Expect the provider's mail hostnames in priority order. If there is no explicit MX, look for an implicit result; priority 0 with exchange . means the domain intentionally accepts no email.

Before you act on the result

MX records describe routing only. They do not prove that port 25 is reachable, TLS works, a mailbox exists, or the receiving server will accept a particular message.

Read the MX Record Guide for the technology overview and troubleshooting steps.

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