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MX record
checker

Query any domain's mail exchangers in one click. Review priorities, confirm you have failover coverage, and pinpoint why messages aren't arriving.

MX record lookup

Enter the domain without http:// or www.

§ 01MX records explained

The route every email takes.

MX records tell senders where your mailbox lives — remove them and mail has nowhere to go.

Step 01

Sender looks up MX

Delivery starts with a DNS query: the sending server fetches domain.com's MX records and orders them by priority to decide where to knock first.

Step 02

Connection to port 25

It then opens an SMTP connection to port 25 on the top-priority hostname, falling through to the next MX in order whenever a connection can't be made.

Step 03

Authentication checks

Once connected, your mail server evaluates the incoming message against SPF, DKIM, and DMARC. Depending on your policy, failures get filtered or rejected.

Delivery problems, solved for good.

SPF, DKIM, and DMARC configured for you, plus reputation monitoring that keeps your mail out of the spam folder.

Start with BitelioCheck SPF record

Frequently asked questions

What is an MX record?

MX (Mail Exchanger) records are the DNS entries that tell the world which servers accept email for a domain. Before delivering a message to you@yourdomain.com, the sender's mail server queries DNS for yourdomain.com's MX records and connects to the server they name.

What does the MX priority number mean?

Priority (also called preference) sets the order in which senders attempt delivery — the lowest number goes first, so a priority-10 server is tried before a priority-20 one. If the primary doesn't respond, the sender retries against the next value up. When two records share a priority, senders pick between them at random, which some setups use deliberately for load balancing.

Do I need more than one MX record?

You should, yes. With only one MX record, any outage means mail bounces or sits queued on remote servers. A secondary MX — typically your mail provider's backup exchanger, or a service like Google MX backup — keeps email flowing while the primary is temporarily down.

Why would email delivery fail even if MX records are correct?

Correct MX records don't guarantee delivery. The target server might be down or unreachable on port 25, your IP or domain could sit on a blacklist, misconfigured SPF, DKIM, or DMARC can cause rejections, and content filtering catches the rest. Think of MX as step one — authentication records and sender reputation carry the rest.

Can I change my MX records without losing email?

It's safe if you sequence it carefully. Drop the TTL to 300 seconds a day ahead so changes propagate fast, then publish the new MX records alongside the old ones. Wait for propagation (usually 5–30 minutes at that TTL), confirm mail is arriving at the new server, and only then retire the old records and raise the TTL again.