Look up and validate MX records for email delivery configuration with priority and mail server details.
Enter a domain name to retrieve the MX records that direct inbound email for that domain. The checker reports each mail exchanger hostname with its numeric preference, making it useful for reviewing routing, redundancy, and stale provider entries. MX preference is commonly read backward: a lower number has higher priority. Multiple records with the same preference are peers rather than a sequence, and the existence of an MX record alone does not prove that its server is reachable or accepting mail.
The lookup requests MX resource records at the entered DNS name. Each returned record pairs a preference value with an exchange hostname, such as a provider-operated mail gateway. The result is a set, so displayed row order is less important than the preference numbers. A domain can legitimately publish one MX record, several records, or no explicit MX records.
Sending systems normally try exchangers beginning with the lowest preference value. Records sharing a value have equal preference and can provide parallel destinations. A special null MX consists of preference 0 and exchange "."; it states that the domain accepts no email. That declaration must not be interpreted as an ordinary mail server named by a blank hostname.
No. The lowest preference value identifies the most preferred exchanger. For records with preferences 10 and 20, the exchanger at 10 is attempted before the one at 20 under normal routing. The values express relative order only: changing them to 1 and 2 would preserve the same preference relationship.
No. SMTP defines an implicit fallback to the domain itself when no MX records are present, although successful delivery still requires that name to resolve appropriately and offer SMTP service. This differs from a null MX record, whose exchange is "." and which explicitly declares that the domain does not accept email.
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