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MX Lookup

Are MX records pointing to the right mail servers - before inbound email stops arriving.

Enter a domain - e.g. yourdomain.com

Mail servers

Priority-ordered MX hostnames for your domain

Record validity

Whether MX records resolve correctly

Delivery path

How incoming mail reaches your domain

No account required · Free · Results in under 1s

What is an MX lookup?

Mail server records explained

When MX records point to the wrong host or disappear after a DNS edit, inbound mail bounces silently - often before anyone checks the mail server logs.

An MX lookup queries DNS for Mail Exchange records and priority values that tell senders which servers receive email for a domain. A free MX lookup shows the live routing configuration.

Run a check after switching email providers or editing DNS. Add domains to TotalSiteControl monitoring for alerts when MX records change unexpectedly.

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How to use the MX Lookup

See which mail servers handle a domain in under a minute - no account needed.

  1. Enter the domain

    Type the email domain, for example yourdomain.com. That is the part after @ in addresses.

  2. Run the MX lookup

    Click the lookup button. We fetch MX records and priorities published in public DNS.

  3. Read the mail hosts

    Confirm the hosts and priorities match your mail provider. Fix mismatches before users report bouncing mail.

Typical MX issues and solutions

Why mail stops after provider or DNS changes.

No MX records

Senders cannot find a mail host. Messages bounce or queue until records appear.

Publish provider MX values

Add the exact MX hostnames and priorities from your mail host, wait for TTL, then re-check.

Old MX still published

Some mail still goes to a previous provider after a migration.

Remove obsolete MX entries

Keep only current provider hosts, lower TTL before cutover, and verify with a fresh MX lookup.

Priority order looks wrong

Backup hosts receive mail first, or a deprecated host has a lower preference number than primary.

Set priorities per provider docs

Lower numbers are tried first. Align priorities with your provider’s recommended order, then re-check.

What you get with monitoring

Comprehensive data

Certificate, DNS, and reachability history in one place.

Trusted & accurate

Checks run from our servers - the same path users hit.

Fast & easy

Turn a one-off check into monitoring in under a minute.

Global coverage

External probes so internal network blind spots do not hide issues.

Instant alerts

Email and Telegram when something fails or is about to expire.

30 monitors free

Start free - no credit card required to begin monitoring.

Get 30 monitors FREE

Start free monitoring with email alerts. No credit card required.

MX lookup tips

Keep mail routing boring and predictable.

Tip #1 Check MX after every email migration

Provider switches fail quietly when old MX linger. Confirm public DNS matches the new host.

Tip #2 Verify SPF and DKIM next

MX alone does not authenticate mail. Pair this tool with SPF and DKIM checks.

Show more tips Show less tips
Tip #3 Use the apex email domain

Lookup the domain people send to, not an arbitrary subdomain, unless that subdomain has its own mail.

Tip #4 Monitor MX changes

Unexpected MX edits are a common hijack and misconfig signal. Alerts help you react fast.

Frequently asked questions

What is an MX lookup?

It queries DNS for Mail Exchange records that tell the internet which servers receive email for a domain.

Is this MX lookup free?

Yes. Check any public domain instantly - no signup, no credit card, and no limit on one-off lookups.

Why is my email not delivering?

Wrong or missing MX records are a common cause - inbound mail never reaches your provider servers until DNS is fixed.

What does MX priority mean?

Lower numbers are tried first. Higher numbers are backups used when the primary mail server is unavailable.

Why are there multiple MX records?

For redundancy - if one mail server is down, senders try the next priority until one accepts the message.

Can I use MX lookup after switching to Google or Microsoft 365?

Yes - run a lookup after migration to confirm MX points to your new provider hostnames, not the old mail server.

Do I still need SPF and DKIM if MX is correct?

Yes. MX routes incoming mail; SPF and DKIM authenticate outgoing mail. Check all three for reliable delivery.

How often should I check MX records?

After email provider changes or DNS edits. Monitoring alerts when MX records change unexpectedly.

Protect your email deliverability

Monitor MX, SPF, and DNS records with free alerts.

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