What is an MX record lookup?

It queries DNS for MX records and lists the mail exchanger hostnames that accept email for a domain, with priorities.

What is an MX record?

An MX (Mail Exchanger) record points to the hostname of a server that receives SMTP mail for the domain, plus a priority value.

Sending servers sort MX records by priority ascending. The lowest number is preferred; equal or higher numbers are fallbacks.

Yes. Multiple MX entries with different priorities provide redundancy and load distribution across mail providers.

MX targets must be hostnames, not bare IP addresses. Those hostnames resolve via A or AAAA records separately.

Check SPF, DKIM, DMARC, firewall port 25, and provider-side acceptance rules. MX alone does not guarantee delivery.

Yes, once traffic is stable. Leaving stale MX records can split mail between old and new providers.

Common values are 300–3600 seconds. Lower TTL before migrations speeds rollback if something goes wrong.

Subdomains need their own MX unless mail routing policies say otherwise. Always query the exact domain that receives mail.

This tool shows only MX records for a quick mail-routing answer without other DNS types.

Standards discourage MX targets that are CNAME aliases. Use a hostname with direct A/AAAA instead.

The domain may not accept mail, use a child domain for mail, or DNS may be misconfigured. Verify NS delegation too.

Yes. IP Checker Online provides MX lookups at no cost.

Before and after email provider migrations, when mail stops arriving, and during domain onboarding audits.

Yes. SPF, DKIM, and DMARC live in TXT records. Use TXT Record Lookup or the SPF DKIM DMARC Checker after MX verification.

DNS Tools

See which mail servers accept email for a domain (MX records).