What Is an MX DNS Record?

MX record explained

An MX record tells other mail systems where to deliver email for your domain

Each MX record contains a mail-server hostname and a priority number. Lower numbers are normally tried first. The destination provider must already be configured to accept mail for the domain, so copying an MX value alone does not create a mailbox.

MXMail destinationA hostname, not a mailbox
PRIORITYLower is preferredUsed when several records exist
RELATEDSPF, DKIM, DMARCSeparate sender-authentication records

What are the parts of an MX record?

Host or name

The domain receiving the mail. DNS interfaces may show the root as @, a blank field or the full domain name.

Destination

The fully qualified hostname of the receiving mail server supplied by the email provider. Do not invent this value.

Priority

A number that orders multiple mail destinations. The lowest number is preferred; equal values may share delivery attempts.

TTL

The caching period for the DNS answer. Lowering it shortly before a planned migration can help, but existing caches still expire on their previous timing.

How do I change MX records without losing email?

  1. 1
    Confirm the authoritative DNS provider

    Edit records where the active nameservers host the zone, not merely where the domain was registered.

  2. 2
    Copy the provider’s complete set

    Obtain every required MX, SPF, DKIM and verification value from the email provider.

  3. 3
    Check before deleting

    Understand which old records must be replaced. Removing an active route too early can interrupt delivery.

  4. 4
    Test both directions

    Send from an outside service and reply. Check message headers and provider diagnostics if the route is unclear.

How should common arrangements look?

ArrangementMeaning
One MX recordAll incoming mail is directed to one provider hostname
Several prioritiesThe lowest number is preferred and higher-numbered records provide alternative routes
Several equal prioritiesMail systems may distribute attempts between equivalent destinations
No MX recordMail delivery may fail or fall back unpredictably; configure the provider’s required records

MX record questions

Does an MX record affect my website?

Not directly. Website traffic normally uses A, AAAA or CNAME records. Replacing the complete zone or nameservers can affect both services.

Does it control outgoing mail?

No. Mail apps send through an authenticated SMTP service. MX records primarily publish where other systems should deliver incoming mail.

Why does a DNS checker show the old value?

Resolvers cache DNS answers until their TTL expires. Confirm the change at the authoritative nameservers and allow existing caches to refresh.

Change mail routing carefully

Use the exact records supplied by the email provider

Record the old zone and test incoming and outgoing mail after the change.

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