MX record lookup

What this MX lookup shows

Every domain that receives email publishes one or more MX records. This tool reads them straight from DNS and, for each mail server, shows:

• Priority — the order in which other servers try to deliver;
• IP address — where the host name points, and whether it is reachable from the internet;
• Reverse DNS — the PTR name of that IP, which helps identify the operator;
• Email provider — recognised automatically for Google Workspace, Microsoft 365, Zoho, Proton, Fastmail and many others.

Common MX problems

• No MX record: mail falls back to the domain's A record and is usually lost. Add the MX records your email provider gives you.
• MX pointing to an IP address or a CNAME: not allowed by the standard and rejected by some senders.
• Old records left behind after moving to a new provider: some mail keeps going to the old server. Remove MX records you no longer use.
• Host names that do not resolve: a typo in the target host means mail cannot be delivered at all.

MX records and email deliverability

MX records decide where you receive mail, but they also matter when you send: bounce messages and replies go to your domain, and some spam filters check that a sending domain can receive mail. If you send newsletters or transactional email, make sure your domain has working MX records and valid SPF, DKIM and DMARC records. Our guide to SPF, DKIM and DMARC explains how they fit together.

Before you send to a list, you can also check that each recipient's domain has mail servers — that is one of the checks in InboxRoads bulk email verification.