MX Records Explained: How Email Routing Works

MX records (Mail Exchange records) are the DNS entries that tell the internet where to deliver email for your domain. Without them, nobody can send you email. This guide explains what they are and how to configure them.

What Is an MX Record?

When someone sends you an email, their mail server looks up the MX record for your domain to find out which server should receive the email. The MX record points to a mail server (like Google's servers for Gmail, or Microsoft's servers for Outlook).

MX Record Structure

Each MX record has two parts:

• Priority (Preference): A number that determines which server to try first (lower number = higher priority). Useful for backup mail servers.
• Mail Server (Exchange): The hostname of the server that receives email for your domain.

MX Records for Common Email Providers

How to Add or Update MX Records

1. Log in to your domain registrar or DNS provider.
2. Find the DNS Records or DNS Management section.
3. Delete any existing MX records (if you're changing providers).
4. Add new MX records as specified by your email provider:
   • Type: MX
   • Host/Name: @ (root domain)
   • Priority: as specified
   • Value: the mail server hostname
5. Save. DNS propagation takes up to 48 hours (usually much faster).

How to Check Your MX Records

Use a free MX record lookup tool to verify your records are correct:

• MXToolbox (mxtoolbox.com) — type your domain and click MX Lookup
• Google Admin Toolbox — check-mx.appspot.com