MX record checker
Enter your domain to see which servers receive your mail, their priority order and the IP addresses each one resolves to. We'll flag unresolvable hosts and non-standard setups.
No signup, no email required. Only public DNS records are read.
What is an MX record?
An MX (Mail Exchanger) record is the DNS record that tells senders which server should receive mail for your domain. When someone emails you, their server first asks for your domain's MX record and delivers the message to the host it names.
MX records only concern RECEIVING mail. Sending is governed by SPF, DKIM and DMARC; changing your MX has no effect on the deliverability of mail you send.
What does the priority number do?
Every MX record carries a number in front of it: the priority. Lower means higher priority — a sender tries the lowest-numbered host first and moves on to the next if it can't connect.
The absolute values don't matter, only their order relative to each other: 10 and 20 behave exactly like 5 and 50. If several records share the same priority, the sender picks among them at random — a normal configuration used for load sharing.
Is a single MX record enough?
Usually yes. A backup MX exists to accept mail temporarily when the primary is unreachable and forward it later. But modern senders already queue undeliverable mail for days and keep retrying, so short outages don't need a backup MX.
A poorly configured backup MX can even become a preferred entry point for attackers, because its spam filtering is usually weaker. That's why most large providers run a single MX — google.com included.
An MX record shouldn't point to a CNAME
The standard requires an MX target to be a hostname with A or AAAA records directly. Pointing it at a CNAME is a common mistake: most senders still deliver, some reject, and troubleshooting becomes hard.
Likewise, an MX target can't be a bare IP address. Create an A record for your server and point the MX at that name.
Null MX for domains that don't receive mail
If a domain only hosts a website and never receives mail, publishing a null MX is better than leaving MX empty: a single MX record with priority 0 and '.' as the target.
The benefit is that anyone trying to mail you gets an immediate, unambiguous error. With no MX at all, some senders will try delivering to the domain's A record and the message can sit in a queue for days.
Frequently asked questions
How do I look up an MX record?
Enter your domain in the tool on this page; your MX records are listed in priority order and each host is resolved to its IP addresses. From a terminal you can also run 'dig +short MX yourdomain.com'.
I changed my MX record — when does it take effect?
After the record's TTL, typically 300 to 3600 seconds with most DNS providers. Don't shut the old server down immediately: mail may keep arriving there for a few hours during the transition.
What priority value should I use?
The absolute value doesn't matter, only the ordering. 10 is a common choice for a single server. If you add a backup, give it a higher number such as 20.
I have MX records but I'm not receiving mail — why?
The most common causes are: the host named in the MX has no A record (the tool shows this as 'does not resolve'), port 25 is blocked on the server, or the mailbox hasn't been created yet at your provider. If the MX looks correct, the problem is on the server side rather than in DNS.
Is this tool free? Do I need an account?
It's completely free and requires no account or email address. It only reads public DNS records.