MX Record Lookup Tool

Check MX records instantly across multiple public resolvers to validate your email routing.

How to troubleshoot email delivery with an MX Lookup

If your domain isn't receiving emails, verifying your MX (Mail Exchange) records is the first step. Enter your domain name above to query its active mail servers across global DNS resolvers. This helps identify routing misconfigurations, priority conflicts, or propagation delays.

Interpreting your MX results

  • No MX Records Found: If the lookup returns nothing, your domain cannot receive emails. Senders might fall back to the A record, but this is highly unreliable.
  • Understanding Priorities: The number next to your mail server (e.g., 10 mail.example.com) is the preference value. Lower numbers have higher priority. Mail is routed to the lowest number first.
  • Inconsistent Results: If different resolvers return different mail servers, your recent DNS changes are still propagating. This can cause some emails to deliver to your old provider.
  • Next step: Email Authentication. Correct MX records only ensure you receive mail. To ensure your outgoing mail doesn't go to spam, use our Email DNS Check to validate your SPF and DMARC setup.

MX record lookup for mail delivery

MX records control where inbound email is delivered. Each MX entry includes a hostname and a priority value; lower numbers are preferred. A correct MX setup ensures that mail servers can accept messages for your domain and provides failover if a primary server is down. This lookup shows the full MX set across resolvers so you can verify order and ensure all hosts are reachable.

Common mail issues are caused by missing MX records, using an incorrect hostname, or pointing to a host that does not accept mail. Also check that the target hostnames have valid A or AAAA records. If you use a hosted email provider, the MX records are usually documented and must match exactly. Even a small typo can cause mail delivery to fail.

If you need related checks, try Check Email DNS check online and Blacklist/RBL check lookup.

Priority determines which server should be tried first. Lower values are preferred. If the lowest priority host is unreachable, the sender will attempt higher priority hosts.

No. MX records must point to hostnames. Those hostnames must then resolve to A or AAAA records.

Multiple MX records provide redundancy and sometimes load distribution. If you see multiple values with the same priority, senders may choose any of them.

Some mail servers will fall back to the A record for delivery, but this is not reliable and not recommended. Explicit MX records are best practice.

You can connect to the mail server on port 25 to confirm it responds, and verify correct SMTP banners. Also check SPF and DMARC to improve deliverability.

It usually means propagation is incomplete or TTL caches differ. Check the authoritative name servers and wait for caches to expire.