Source: https://uptimeify.io/resources/platform-and-support/glossary/mx-record

# MX Record

> An MX (Mail Exchange) record is a DNS record that tells the internet which mail servers are responsible for receiving email for a domain.

When someone sends mail to your domain, their server looks up your MX records to find where to deliver it. A missing, wrong, or unreachable MX record means inbound email silently fails, which is why MX monitoring is a core part of mail reliability.