MX Lookup
Where does your email actually go?
Enter a domain to see which servers accept its email, in priority order, with their IP addresses and the service they belong to. If mail isn't arriving, the cause and the fix are on the same screen.
Not Receiving Email? Find the Cause
Most incoming-mail problems come from the MX record: there isn't one, it points to a server that doesn't exist, or an old provider's record was left behind after a switch. Pick the symptom you see to get its cause and fix.
No email arrives at all
Without an MX record, senders try the domain's web server and the message usually bounces. If there is a record, check that the server name resolves to an IP address. Add the MX values your email provider gives you in your DNS panel; with Atak Domain Business Email they're added automatically.
See Business EmailI switched providers, but mail still goes to the old one
Either the old provider's MX record is still there, or its TTL hasn't expired yet. Delete the old records so only the new provider's values remain; the result changes once the TTL (usually an hour) runs out. Keep the old mailbox open until the switch is complete.
Some emails arrive, others go missing
If MX records of different providers sit side by side, senders deliver to a different one each time and part of your mail lands in a mailbox you don't use. Check the service names in the result and keep only the records of the service you use.
The MX record contains an IP address
An MX value can't be an IP address; it must be a host name (RFC 5321). Put the IP in an A record such as mail.example.com and use that name in the MX record.
I changed the record, but nothing changed
A DNS change stays invisible in caches until the old record's TTL expires, so wait that long. To make sure you edited the right panel, check the domain's NS records: records are managed wherever the NS records point.
DNS LookupIncoming mail is fine, but my sent mail lands in spam
That isn't an MX problem; MX only handles incoming mail. Whether your sent mail is trusted depends on your SPF, DKIM and DMARC records. Start with SPF: every service you send from must be listed in it.
SPF Record CheckerWhat Is an MX Record?
An MX (Mail Exchanger) record tells the DNS which server should receive email sent to a domain. A message to info@example.com goes to the server named in example.com's MX record.
A domain can have several MX records. The server with the lowest priority number is tried first; if it doesn't answer, the next one takes over. MX only handles incoming mail; trust in outgoing mail comes from SPF, DKIM and DMARC.
- Sending serverLooks up the recipient's MX record
- MX recordLists the servers in priority order
- Your mail serverAccepts the message and files it in your mailbox
How to Read an MX Record
example.com.Domain: The domain whose email is being routed. The trailing dot marks a fully qualified name; most DNS panels leave it out.3600TTL: How long the record may be cached, in seconds. 3600 is one hour; a change is visible everywhere at the latest when it runs out.MXRecord type: Says the record is for routing email.10Priority: The lower number is tried first. With 10 and 20, mail goes to the 10 server first.mx1.example.com.Mail server: The name of the server that accepts the mail. It can't be an IP address; the name needs its own A or AAAA record.
The result also shows each server's IP addresses and which email service it belongs to. The service name is the quickest way to tell whether your email switch is complete.
MX Records for Popular Email Services
When moving to a new email service, compare these values with the ones in its setup screen and delete the old provider's records.
| Service | Priority | MX value |
|---|---|---|
| MailLB (Atak Domain) | 10 · 1000 | smx.maillb.com |
| Google Workspace | 1 | smtp.google.com |
| Microsoft 365 | 0 | example-com.mail.protection.outlook.com |
| Yandex 360 | 10 | mx.yandex.net |
| Zoho Mail | 10 · 20 · 50 | mx.zoho.com · mx2.zoho.com · mx3.zoho.com |
In Microsoft 365 the server name is unique to your domain; copy it from the admin center. Google Workspace's older five-record setup (ASPMX.L.GOOGLE.COM) still works. With Atak Domain Business Email the MX, SPF and DKIM records are added for you.
Frequently Asked Questions
The most common questions about MX records, priority and email routing.
- Yes. Several records let mail fall back to another server when one doesn't answer. They should all belong to the same email service; if records of different providers mix, part of your mail ends up in the wrong mailbox.
- The lower number comes first: a priority 10 server is tried before a priority 20 one. Servers with the same priority are picked at random, which spreads the load.
- By the standard, the sender tries the address in the domain's A record. Usually only a web server runs there, so the message bounces. If the domain will never receive email, publishing a null MX (
0 .) is cleaner. - Google Workspace needs one record: priority 1, value
smtp.google.com. Yandex 360 uses priority 10 andmx.yandex.net. Microsoft 365 uses priority 0 and a…mail.protection.outlook.comhost unique to your domain. - On Windows run
nslookup -type=mx example.com; on macOS and Linux rundig MX example.com +short. These may answer from your own resolver's cache; this tool fetches a fresh result from Google Public DNS. - A null MX is a single MX record with the value
0 .(RFC 7505), meaning "this domain accepts no email". On parked domains or domains used only for a website, it saves senders from retrying in vain.
Rather not deal with email DNS records?
Atak Domain Business Email adds the MX, SPF and DKIM records for you, with support every day; from $0.99 a month.