MX record

MX Lookup

Look up a domain's MX records - the mail servers that receive its email - with priorities, and check that each one resolves to a real server.

One record is only part of it

MX, SPF, DKIM, DMARC, MTA-STS, TLS-RPT, DNSSEC and BIMI all decide together whether your mail is trusted. The full report reads every one of them and hands you the fix.

Run the full domain check

About these results

This tool reads a domain's public MX records at the moment of the lookup and checks that each mail server hostname resolves. Results reflect current public DNS and can be affected by caching and propagation (up to 24-48 hours). Guidance is general and not a substitute for your provider's official instructions. We don't store the domains you check.

Reference

How MX works

What the record is for, how to read the result, and what to do about each problem.

What is an MX record?

MX records tell other mail servers where to deliver email for your domain. Each has a priority - senders try the lowest number first, then fall back to higher numbers.

Implicit MX and null MX

Implicit MX: no MX but an A/AAAA record - senders fall back to that address (RFC 5321). Explicit MX is more predictable.
Null MX: a single 0 . record (RFC 7505) - the domain sends/receives no mail.

Common problems and fixes

No MX records: add your provider's MX records, or publish a null MX if the domain shouldn't handle mail.
MX host doesn't resolve: point each hostname at a valid server or remove stale entries.

Questions

Frequently asked

What is an MX record?

An MX (Mail eXchanger) record tells other mail servers which servers receive email for your domain. Each has a priority - the lowest number is tried first.

Can a domain have more than one MX record?

Yes. Multiple MX records with different priorities provide redundancy: if the lowest-priority server is unavailable, senders try the next one.

What is a null MX?

A null MX (a single MX record with a '.' host, RFC 7505) explicitly says the domain does not send or receive email - correct for parked domains and reduces spoofing.

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