MX Record Lookup Tool
Discover the mail servers responsible for receiving email for any domain. View MX records and their priorities.
What Are MX Records?
MX (Mail Exchange) records are DNS entries that specify which mail servers are responsible for accepting email on behalf of a domain. When someone sends an email to [email protected], the sending server queries DNS for the MX records of example.com to determine where to deliver the message.
Each MX record has two components: a priority number and a mail server hostname. Lower priority numbers indicate preferred servers. If the primary server is unavailable, the sending server tries the next one in priority order. This system provides redundancy and ensures email delivery even during server outages.
Understanding a domain's MX configuration helps diagnose email delivery problems, verify that a domain is set up to receive email, and identify which email provider a company uses (Gmail, Microsoft 365, Zoho, etc.).
Why Look Up MX Records?
MX record lookups are essential for email deliverability analysis. A domain without MX records cannot receive email, making any address at that domain invalid. Additionally, the MX records reveal the email infrastructure — for example, MX records pointing to google.com indicate the domain uses Google Workspace.
System administrators use MX lookups to troubleshoot email routing issues, verify DNS configuration after migrations, and audit email security settings. Marketers use them to understand prospect email infrastructure and predict deliverability patterns.
Frequently Asked Questions
What does the priority number mean?
The priority (or preference) number determines the order in which mail servers are tried. A server with priority 10 is tried before one with priority 20. Multiple servers with the same priority receive email in a round-robin fashion.
Can a domain without MX records receive email?
Technically, if a domain has an A record but no MX records, some mail servers will attempt delivery to the A record's IP address. However, this is unreliable and most properly configured domains have explicit MX records.
How often do MX records change?
MX records typically change only during email provider migrations or infrastructure updates. Most domains keep the same MX configuration for months or years. Changes propagate according to the record's TTL (Time To Live), usually within hours.