What the answer means
- Mail servers
- The domain lists servers that take its mail. It can receive email, though that says nothing about any one mailbox.
- No MX, but an address record
- Senders fall back to the domain's address record (RFC 5321). Mail may arrive, but most domains that really take mail set MX records.
- Accepts no mail
- The domain publishes a null MX (RFC 7505): it says outright that it takes no email. An address there can't work.
- No mail servers
- No MX and no address record. Mail to this domain has nowhere to go.
How to read the list
Lower priority numbers are tried first. Servers with a higher number are backups, used when the first ones don't answer. Two servers with the same number share the load.
The provider next to a server is our guess from its host name, and only for hosts we recognise. A Google or Microsoft host usually means a real mailbox service. A security gateway like Mimecast or Proofpoint usually means a company, with its real mail server hidden behind it. A forwarding service means mail is passed on to another inbox.
MX records can't tell you whether a mailbox exists, and a throwaway service has MX records too. We look these up live from public DNS and don't connect to the servers.
What happens to what you type
Paste an address and, with JavaScript on, only the part after the @ leaves your browser. Without JavaScript the form sends what you typed to our server, which reduces it to the domain and opens that domain’s page. We don’t save what you check here, with one exception: the domain age tool keeps the registry’s answer for a domain in memory for up to 24 hours, so repeat checks don’t go back to the registry. It’s free, and limited to 30 checks a minute per visitor.
Need this on every signup? The API checks format, mail servers, disposable domains, role addresses and relays in one call, and the first 100 checks a month are free.
Free email provider checkerEmail forwarder checkerDomain age checker