MX Record Lookup

Query MX records, mail server IPs, SPF authentication, and DMARC policies for any domain.

MX Records SPF Validation DMARC Policy

Understanding MX Records

MX (Mail Exchange) records are essential for email delivery. Learn how they work and how to configure them correctly.

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What are MX Records?

MX records tell the world which mail servers accept email for your domain. Without them, you cannot receive email.

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Priority Levels

Each MX record has a priority number. Lower numbers have higher priority. Servers try the lowest number first, providing failover and redundancy.

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Redundancy

Having multiple MX records ensures you don't miss emails if your primary server goes down. Backup servers queue mail until the primary is back.

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TTL (Time To Live)

TTL determines how long DNS resolvers cache your MX records. Lower TTL allows faster updates during migrations, while higher TTL reduces DNS query load.

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SPF & DMARC

While MX handles incoming mail, SPF and DMARC protect your outgoing mail reputation. Always configure them alongside your MX records.

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Common Issues

Misconfigured priorities, pointing to IP addresses instead of hostnames (CNAMEs are also not allowed for MX), or missing records can cause delivery failures.

Frequently Asked Questions

What are MX records and why are they important? expand_more

MX (Mail Exchange) records are DNS entries that specify which mail servers are responsible for receiving email on behalf of your domain. Without MX records, your domain cannot receive email. They are essential for email delivery and are checked by sending mail servers to determine where to route messages.

How does MX record priority work? expand_more

MX priority determines the order in which mail servers are tried. LOWER numbers = HIGHER priority. For example, priority 10 is tried before priority 20. If the highest priority server (lowest number) is unavailable, the sending server tries the next priority level. This provides failover and redundancy for email delivery.

What is SPF and why do I need it? expand_more

SPF (Sender Policy Framework) is a DNS TXT record that specifies which mail servers are authorized to send email on behalf of your domain. It helps prevent email spoofing and improves deliverability by allowing receiving servers to verify that incoming mail from your domain comes from authorized servers. Format: 'v=spf1 include:_spf.google.com ~all'

What is DMARC and how does it protect my domain? expand_more

DMARC (Domain-based Message Authentication, Reporting and Conformance) is a DNS TXT record at _dmarc.yourdomain.com that tells receiving servers what to do with emails that fail SPF/DKIM checks. It prevents email spoofing and phishing by specifying policies (none, quarantine, reject) and provides reporting on email authentication failures.

Why does my domain show 'No MX records found'? expand_more

This means your domain does not have MX records configured in DNS, so it cannot receive email. To fix this: 1) Log into your DNS provider (domain registrar or hosting), 2) Add MX records pointing to your mail server, 3) Wait 1-48 hours for DNS propagation. If you use Gmail/Microsoft 365, consult their documentation for the correct MX records.

Should I have multiple MX records? expand_more

Yes, best practice is to have at least 2-3 MX records for redundancy. If your primary mail server (lowest priority number) goes down, email will automatically be routed to the backup servers. For example, Google Workspace uses 5 MX records with priorities 1, 5, 5, 10, and 10 for high availability.

How do I verify my email configuration is correct? expand_more

Use this MX lookup tool to check: 1) MX records exist and resolve to mail servers, 2) Each MX hostname resolves to valid IP addresses, 3) SPF record is present and includes your mail provider, 4) DMARC record is configured with appropriate policy. Test by sending email to and from your domain.

What are common MX record mistakes? expand_more

Common errors: 1) Pointing MX to an IP address instead of hostname (must be hostname), 2) Forgetting trailing dot in some DNS systems, 3) Using same priority for all records (defeats redundancy), 4) Not updating MX records when changing email providers, 5) Typos in hostnames, 6) Not waiting for DNS propagation (up to 48 hours).

How long does MX record propagation take? expand_more

DNS changes typically propagate within 1-4 hours, but can take up to 48 hours globally. Factors affecting speed: TTL (Time To Live) of old records, DNS provider infrastructure, ISP DNS caching. You can reduce propagation time by lowering TTL before making changes (e.g., to 300 seconds), making the change, then raising TTL back to normal.