What is an MX Record?
An MX (Mail Exchange) record is a type of DNS record that tells the internet which mail server is responsible for receiving email on behalf of a domain. When someone sends an email to user@example.com, the sending server looks up the MX records for example.com to find out where to deliver the message.
Each MX record has two components: a priority (lower number = higher priority) and a mail server hostname. Most domains have multiple MX records for redundancy — if the primary server is unavailable, mail is delivered to the next server in priority order.
Example MX Records
example.com. MX 10 mail1.example.com.
example.com. MX 20 mail2.example.com.
example.com. MX 30 mail3.example.com.
MX Records and Email Validation
MX record verification is a fundamental part of email validation. If a domain has no MX records, it cannot receive email — meaning any email address at that domain is guaranteed to bounce. Checking MX records is one of the fastest, most reliable checks in the validation pipeline.
MX records also reveal which email provider a domain uses (Gmail, Outlook, custom server, etc.), which is useful for understanding deliverability characteristics and identifying disposable email services that share common mail infrastructure.
Check any domain's MX records instantly with Mailchk's free MX Lookup tool.