MX Lookup

What MX records actually do

MX records tell the world where a domain receives email. They do not control sending. If you are missing MX records, other mail servers may not know where to deliver inbound mail.

Common real-world issues

• No MX records: inbound mail fails or bounces for that domain.
• Wrong target: mail goes to an old provider after a migration.
• Mixed providers: partial migrations where some mail lands in the wrong inbox.
• MX is fine but mail still fails: then it’s usually SPF/DKIM/DMARC, reputation, or content filters.

Does MX affect email deliverability?

MX records do not control sending reputation directly, but they matter for:

• Receiving bounces and feedback loops correctly
• Inbox placement during provider migrations
• Avoiding silent mail loss when MX points to old systems

If inbound mail is broken, SPF/DKIM/DMARC won’t save you. MX must be correct first.

What to do next

1. Confirm MX points to the provider you expect.
2. Check SPF, DKIM, and DMARC for the same domain.
3. If you’re debugging a delivery problem, confirm results in headers with the Email Header Analyzer.