How to Use the MX Lookup
Check the MX records of a domain in one lookup, then compare the mail servers with your provider’s settings.
- Enter the domain part of the address, such as example.com, or paste a full email address.
- Select Look up MX to query the MX records and resolve every mail server to its IP addresses.
- Read the table from the lowest priority number upward and compare each host with your mail provider’s setup instructions.
- If no MX record is found, add the records your provider gives you, then run the lookup again.
Email MX Record Lookup
An email MX record lookup shows where mail for a domain is delivered: the mail server hosts, their priority and the addresses behind them.
MX Record Priority
Each MX record carries a preference number, and sending servers try the lowest number first. Records with the same number share the traffic, and higher numbers act as backups. The table is sorted by priority so the primary mail server is always on the first row.
DNS MX Lookup
After reading the MX records, the tool looks up the A and AAAA records of every mail server host. A server without any address cannot receive mail, even though its MX record is published. A listed address still does not prove that the server is reachable or accepts SMTP connections.
Check MX Record Propagation
Answers come from Cloudflare’s public DNS resolver, which may hold a cached copy until the record’s TTL expires. After changing MX records, wait for the old TTL to pass and look up the domain again. The time of each query is listed under the result.
MX Record vs SPF Record
Each approach answers a different question, so the table shows what it establishes and where its limit lies.
| Approach | What it shows | Limit |
|---|---|---|
| MX | Inbound routing | Does not authorize outbound senders |
| SPF | Envelope sender authorization | Does not route inbound mail |
Frequently Asked Questions
What Is MX Lookup?
An MX lookup is a DNS query for the mail exchanger records of a domain. Those records tell sending servers which hosts accept email for the domain and in which order to try them.
Can MX Records Point to Two Servers?
Yes. A domain can publish several MX records, each naming a different server. Equal priority numbers spread the load between them, and different numbers create a primary and a backup.
Can an MX Record Be an IP Address?
No. The target of an MX record must be a hostname, such as mail.example.com. That hostname then needs its own A or AAAA record with the server’s IP address.
Can an MX Record Point to a CNAME?
The DNS standards say an MX target must not be an alias. Some servers follow a CNAME anyway, but others refuse, so point MX records at a hostname with its own address records.
How Do I Know If My MX Records Are Correct?
Compare every host and priority in the result with the values your email provider publishes. Then send a test message from an outside account to confirm that mail arrives.
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