MX Checker

Validate a domain's MX configuration for common problems — not just a list of records.

About this tool — and how it differs from MX Lookup

Our separate MX Lookup tool shows the raw MX records for a domain and resolves each mail server's IP — useful when you just need to see what's configured. This tool instead runs that same data through a set of validation checks, looking specifically for configuration problems: no MX records at all, an MX pointing to an IP address instead of a hostname (invalid per RFC 5321), or an MX target that doesn't resolve.

Common MX problems this catches

  • No MX records — mail cannot be delivered; most receiving servers won't fall back to an A record.
  • MX pointing to a literal IP address — technically invalid; many mail servers reject it outright.
  • MX target that doesn't resolve — a typo, a deleted host record, or a DNS propagation issue.

Related tools:

MX Lookup (raw records) Email Security Checker Reverse DNS Email Checker