What is an MX (Mail Exchanger) record?

An MX record (Mail Exchanger record) tells the internet which servers should receive email for your domain. It's the DNS entry that routes incoming mail.

How it works: When someone sends email to yourname@yourdomain.com, their mail server asks DNS: "Where should I deliver mail for yourdomain.com?" The MX record answers with the address of your mail server.

MX record structure:

Priority: A number indicating preference. Lower numbers are tried first. This enables backup servers.

Host: The mail server address (like mail.yourdomain.com or aspmx.l.google.com for Google Workspace).

Example:
yourdomain.com MX 10 mail.yourdomain.com
yourdomain.com MX 20 backup.yourdomain.com

For email deliverability:

MX records matter for receiving email, not sending
But receiving servers check if your domain can receive (no MX = suspicious)
Mismatch between sending and receiving infrastructure can raise flags

Common setups: Google Workspace, Microsoft 365, or your hosting provider's mail servers. Each has specific MX record requirements.

Think of MX records as your postal address. Without them, letters addressed to your domain have nowhere to go. The mail carrier (sending server) looks up your address (MX record) to make the delivery.