Free MX Record Lookup — Check Mail Server DNS Online
Check mail server (MX) records for any domain
About MX Records & How This Lookup Works
MX (Mail Exchange) records are DNS records that tell the internet which mail servers are responsible for accepting email for your domain. When someone sends an email to [email protected], their sending server performs an MX lookup to find where to deliver the message. Without correctly configured MX records, all email to your domain will fail to deliver. Use this free MX lookup tool to verify your email DNS configuration after migrating to a new mail provider (Google Workspace, Microsoft 365, Zoho, ProtonMail), troubleshoot email delivery failures, check MX record propagation after a DNS change, or confirm that backup mail servers are listed with the right priority numbers. Results are returned in real time directly from authoritative DNS servers — no caching.
Priority Numbers
- Lower = Higher Priority: 10 is tried before 20
- Same Priority: Mail servers are chosen randomly (load balancing)
- Multiple Records: Provide redundancy if primary fails
Common Mail Providers
- Google Workspace: aspmx.l.google.com
- Microsoft 365: *.mail.protection.outlook.com
- Zoho: mx.zoho.com
- ProtonMail: mail.protonmail.ch
Troubleshooting
- No MX Records: Email cannot be delivered
- Wrong Priority: May cause delays or failures
- DNS Propagation: Changes can take 24-48 hours
Frequently Asked Questions
What does priority mean?
MX record priority (also called preference) is a number that tells mail servers which server to use first when multiple MX records exist. Lower numbers have higher priority — a server with priority 10 is tried before one with priority 20. If the priority 10 server is unavailable, mail automatically falls back to the priority 20 server, providing redundancy for email delivery.
Why have multiple MX records?
Multiple MX records provide redundancy for email delivery. If your primary mail server (lowest priority number) is down or unreachable, sending servers will automatically try the next MX record in priority order. This ensures emails are queued and delivered rather than bounced when your primary server has temporary issues. Most email providers (Google Workspace, Microsoft 365) set up multiple MX records for exactly this reason.
How long do DNS changes take?
DNS changes propagate based on the TTL (Time to Live) of the record being changed. Most MX records have a TTL of 3,600 seconds (1 hour) to 86,400 seconds (24 hours). During propagation, different DNS servers around the world may return old or new values. For a complete global update, plan for 24–48 hours. To speed this up, lower your MX record TTL to 300 seconds (5 minutes) a few hours before making changes.
Can I use my domain with Gmail?
Yes. To use Google Workspace (Gmail) with your domain, you need to set specific MX records provided by Google. They look like: ASPMX.L.GOOGLE.COM (priority 1), ALT1.ASPMX.L.GOOGLE.COM (priority 5), ALT2.ASPMX.L.GOOGLE.COM (priority 5), and two more at priority 10. After setting these records, email sent to @yourdomain.com will be delivered to Gmail. Use our MX Lookup tool to verify your Google Workspace MX records are correctly configured.
What is an MX record?
An MX (Mail Exchange) record is a DNS record that specifies which mail server is responsible for receiving email for a domain. When someone sends an email to [email protected], their mail server performs a DNS MX lookup for example.com to find where to deliver the message. Without a valid MX record, email delivery to your domain will fail and senders will receive bounce messages.
What happens if there's no MX record for a domain?
If a domain has no MX record, sending mail servers will typically fall back to trying the A record (the domain's IP address) on port 25. However, most modern mail servers do not accept this fallback, resulting in email delivery failures and bounce messages to senders. If you're migrating email providers and temporarily have no MX record, emails sent during that window may be lost or bounced.
How do I verify my email is correctly configured?
To verify correct email configuration: use our MX Lookup tool to check your MX records exist and point to the right servers; send a test email from an external address and verify it's received; check SPF records (TXT record) to ensure authorized senders are listed; verify DKIM records are published (look for a TXT record with 'dkim' in the subdomain); and check your DMARC record to confirm email authentication policy is in place.
What is the difference between MX and A records for email?
MX records specifically define which server accepts incoming email for a domain. A records map a domain or subdomain to an IP address and are used for web traffic, not email routing. Email delivery relies on MX records — mail servers look up MX records, not A records, when delivering email. Your mail server (e.g., mail.example.com) will have its own A record pointing to its IP, and your domain's MX record will point to that mail server hostname.
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