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MX Lookup
See which mail servers receive email for a domain, in priority order, and which provider runs them.
About MX Lookup
An MX lookup shows the mail exchanger records of a domain: the servers that accept email for it, in the order senders try them. It tells you which provider handles a domain's mail, helps you confirm a migration to a new email service, and explains bounces caused by missing or wrong records. The report also checks SPF, DKIM, DMARC and MTA-STS, which decide whether mail from the domain is trusted.
What an MX lookup shows
Every domain that receives email publishes MX records naming its mail servers, each with a priority number. Senders try the lowest number first. This lookup lists the servers, recognizes common providers from their hostnames (Google Workspace, Microsoft 365, Zoho, Proton, Fastmail, iCloud, Cloudflare Email Routing and others), and detects a null MX that says the domain takes no mail.
Checking a migration to a new email provider
- Replace the old MX records with the ones your new provider gives you, and remove any you no longer need.
- Run this lookup and confirm only the new servers appear.
- Update SPF to include the new provider and set up its DKIM key, then check both in the same report.
DNS changes can take a while to reach every resolver. Our DNS lookup lets you query Cloudflare and Google directly.
Sources: RFC 9989 (DMARC), RFC 7208 (SPF), RFC 6376 (DKIM), RFC 8461 (MTA-STS), Google email sender guidelines.
Frequently asked questions
How do I look up MX records?
Enter a domain or an email address above. The lookup returns the mail servers listed in the domain's MX records, sorted by priority, and names the provider when the servers belong to a known service such as Google Workspace or Microsoft 365.
What does MX priority mean?
Each MX record has a number. Sending servers try the lowest number first and fall back to higher numbers if it does not answer. Records with the same number share the load.
What does an MX record of 0 . mean?
A single MX record with priority 0 and a target of a dot is a null MX. It says the domain accepts no email at all, so senders can fail immediately instead of retrying.
Why does my domain have no MX records?
Either email was never set up for it, or the records were removed when the domain moved. Without MX records, mail to the domain will usually bounce. Add the records your email provider gives you, then check again here.