Deliverability
MX record lookup
List the MX records for any domain with priorities, TTLs, and automatic identification of the email provider behind them.
Enter a domain to list the mail servers that accept its email.
Instructions
How to use this tool
- 01Enter a domain like example.com and click Look up MX records.
- 02The tool queries the domain's MX records over DNS-over-HTTPS and sorts them by priority.
- 03Read the results: lower priority numbers are tried first, and equal numbers share the load.
- 04Use the detected provider to confirm the domain's mail is hosted where you expect.
Background
What MX records are
MX (Mail Exchange) records are the DNS entries that name the servers accepting email for a domain. Each record pairs a hostname with a priority number: delivery is attempted at the lowest number first, and records sharing a number are used in rotation. A domain with no MX records generally cannot receive mail, though some servers fall back to the domain's A record.
The hostnames usually reveal the provider: aspmx.l.google.com means Google Workspace, and hostnames under mail.protection.outlook.com mean Microsoft 365. This tool recognizes the common patterns for you.
Background
MX records and deliverability debugging
MX lookups answer the receiving half of email problems. Bounces that say no valid hosts or DNS failure usually mean broken or missing MX records on the recipient domain. When you migrate email providers, the switchover is literally replacing MX records, and lingering old entries cause mail to split between systems.
MX records do not affect your ability to send. Sending reputation is governed by SPF, DKIM, and DMARC on your domain, which the other checkers in this hub cover.
FAQ
Frequently asked questions
What does the MX priority number mean?
It is a preference order: mail servers try the lowest number first and move to higher numbers only on failure. Records with equal priority share the load roughly evenly.
Can a domain receive email without MX records?
Sometimes. If no MX exists, some senders fall back to the domain's A record, but the behavior is inconsistent and many servers simply bounce. Any domain meant to receive mail should publish explicit MX records.
How long do MX record changes take to apply?
Until the old record's TTL expires, commonly between five minutes and 48 hours. Lower the TTL before a planned migration so the cutover propagates quickly.
Do MX records affect sending email?
No. MX records only govern receiving. Whether your outbound mail is trusted depends on SPF, DKIM, and DMARC, plus your sending IP and domain reputation.
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