Website diagnostics
MX Lookup & Record Checker
Run an MX lookup and MX record checker with Web Health. Find mail servers, validate priority values, resolve their IP addresses, and inspect email delivery routing for any domain.
Understanding MX Records & Mail Routing
Mail Exchange (MX) records direct incoming emails to the proper mail infrastructure (such as Google Workspace, Microsoft 365, or self-hosted SMTP servers). Verifying your domain's MX records ensures seamless email delivery without lost or delayed messages.
Key MX Record Components
- Host / Target: Fully qualified domain name (FQDN) of the mail server.
- Priority Value: Integer value determining server preference hierarchy.
- IP Resolution: A / AAAA records mapping mail servers to IPv4/IPv6 addresses.
- TTL (Time to Live): Caching duration allowed for DNS resolvers.
Email Infrastructure Best Practices
- Redundant Servers: Configure primary and backup MX servers across distinct subnets.
- Avoid CNAME Targets: Never point MX records to CNAME aliases.
- Test SMTP Port 25: Ensure firewalls do not block inbound SMTP traffic on port 25.
- Pair with Reverse DNS: Set valid PTR records on target mail server IPs.
Frequently Asked Questions
An MX (Mail Exchange) record is a resource record in the Domain Name System (DNS) that specifies the mail server responsible for accepting incoming email messages on behalf of a domain name.