MX Record Lookup
Enter a domain to see the mail servers that handle its email, sorted by priority. The lookup uses DNS over HTTPS and runs entirely in your browser.
How email finds a domain
When a message is sent to you@example.com, the sending server does not magically know where to deliver it. It performs a DNS lookup for the domain's MX (mail exchange) records — the list of mail servers that accept email for that name. Each MX record pairs a hostname with a priority number, and delivery is attempted to the lowest-numbered (highest-priority) server first, falling back to the others if it is unavailable. This tool queries those records through Google's DNS-over-HTTPS resolver and sorts them by priority for you. To see other record types, use the general DNS Lookup tool, and for the basics of the system read what is DNS.
If a domain has no MX records, sending servers may fall back to delivering to its A record (the plain address the domain resolves to). So an empty result does not always mean the domain rejects email — it may simply route mail differently, or not receive email at all. The MX hostnames themselves are a handy clue to the provider: Google, Microsoft 365 and others each use recognisable server names.
Reading MX records is useful for diagnosing email delivery problems, confirming a migration to a new mail provider, or checking that a domain's mail setup looks healthy before you send. As with the other lookups on this site, the query is made from your browser to a third-party public resolver, so you see the live, cache-independent answer. Mail servers also lean heavily on reverse DNS — you can check that with the Reverse DNS Lookup.
Frequently asked questions
What is an MX record?
An MX (mail exchange) record tells the internet which servers accept email for a domain. Each record has a hostname and a priority number. When someone emails you@example.com, the sending server looks up example.com's MX records and delivers to the listed mail servers.
What does the priority number mean?
Priority (also called preference) sets the order servers are tried. A lower number means higher priority, so mail is delivered to the lowest-numbered server first. Equal numbers are used for load balancing. This tool sorts the records by priority for you.
Why does a domain have no MX records?
Some domains do not receive email, and some rely on a fallback: if no MX record exists, sending servers may deliver to the domain's A record instead. A blank result usually just means the domain is not set up to receive mail, or handles it another way.
Can I tell who provides a domain's email?
Often, yes. The MX hostnames usually reveal the mail provider — for instance names ending in google.com point to Google Workspace, and outlook.com or protection.outlook.com point to Microsoft 365. The host is just a clue, not a guarantee.
Want the theory? Read the guides → · Visit the zoo →