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MX Lookup

See which mail servers a domain uses, whether each one actually resolves, who runs them, and whether SPF and DMARC stand behind them.

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MX (Mail Exchange) records tell other mail servers where to deliver email for your domain. Lower priority numbers are tried first. Missing or wrong MX records mean inbound email simply fails.

The check goes past the record itself. Each mail server is resolved, because a hostname that points at nothing is the fault a plain lookup cannot show — the record reads correctly, the zone is valid, and delivery quietly fails. It also names the provider from the hostnames, and reports whether SPF and DMARC are published, since MX records govern only the mail coming in.

InfraNest

DNS and email records, together

InfraNest manages your MX and all other DNS records with live sync and ready-made templates for Google Workspace, Microsoft 365 and Zoho.

Mail presets for Google, Microsoft & Zoho
Live push sync to your provider
SPF, DKIM and DMARC checked on every zone
Drift detection

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Frequently asked questions

#What is an MX record?

An MX (Mail Exchange) record tells other mail servers where to deliver email addressed to your domain. It points at a hostname — never at an IP address — and that hostname needs its own A or AAAA record.

#What does the priority number mean?

Lower is tried first. A sending server attempts the lowest-numbered host, and only falls back to higher numbers if that one does not answer. Two records sharing a number share the load between them.

#What happens if a domain has no MX records?

Inbound mail fails. Some senders fall back to the domain’s A record, but most modern providers simply bounce the message — so a domain that receives email needs MX records published, even if it hosts no website. A domain that deliberately receives none should publish a null MX (0 .) to say so outright.

#Can I see who hosts a domain’s email?

Yes — the result names the provider directly. The MX hostnames give it away: google.com for Google Workspace, outlook.com for Microsoft 365, zoho.eu for Zoho. Where the mail servers sit inside the domain itself, it is reported as self-hosted.

#Do I need SPF, DKIM and DMARC as well?

Yes. MX records get mail in; SPF, DKIM and DMARC are what stop your domain being used to send forged mail out, and they increasingly decide whether your legitimate mail reaches the inbox at all.