How this email host lookup works
Every domain that receives email publishes MX records in DNS: a list of mail servers, each with a priority. When you press Find email host, your browser asks Cloudflare's public resolver for the domain's MX and TXT records over HTTPS (DNS over HTTPS, JSON format). We then match the mail server names against known providers, and read the domain's SPF record (a TXT record starting v=spf1) as a second hint about who sends its mail. Nothing is sent to Volt Ghost.
Common email hosts and their MX records
| Provider | Typical MX host names |
|---|---|
| Google Workspace / Gmail | aspmx.l.google.com, smtp.google.com, alt1.aspmx.l.google.com |
| Microsoft 365 / Outlook | <domain>.mail.protection.outlook.com |
| Zoho Mail | mx.zoho.com, mx2.zoho.com (or .eu, .in) |
| Proton Mail | mail.protonmail.ch, mailsec.protonmail.ch |
| Cloudflare Email Routing | route1.mx.cloudflare.net and similar |
| Fastmail | in1-smtp.messagingengine.com |
| GoDaddy | mx1.secureserver.net |
The provider label comes only from host names and SPF, so treat it as a strong hint rather than proof.
Reading the results
- Priority: senders try the lowest number first and fall back to higher numbers. Equal numbers share the load.
- No MX records: the domain probably doesn't receive email. A "null MX" (a single record pointing to
.) means it explicitly refuses all mail. - Filtering gateway: Proofpoint, Mimecast or Barracuda in the MX list means mail is scanned before reaching the real mailbox provider.
- SPF senders: services the domain authorises to send email for it, such as its mailbox provider and newsletter tools.
Why check a domain's email host?
IT and sales teams use an email server finder to see which platform a company uses before a migration or integration. Senders debug bounces: if a domain's MX points at a server that no longer exists, mail will bounce no matter what. Site owners spot sign-ups from domains that can't receive mail, which is common in bot traffic. And if an email arrived from an unfamiliar domain, checking its email host shows whether a mainstream provider runs it. For a raw MX record listing plus a disposable-domain check, use our MX lookup; to check whether an address is from a temp mail service, use the disposable email checker. Curious about the temp mail side? Read what is temp mail.
Questions
How do I find out who hosts a domain's email?
Look up the domain's MX records. They name the mail servers that receive its email, and those host names usually reveal the provider: for example aspmx.l.google.com is Google Workspace and *.mail.protection.outlook.com is Microsoft 365. This tool does that lookup and names the provider for you.
Can I look up the email host from an email address?
Yes. Paste the full address and the tool uses the part after the @. For free mail like gmail.com you'll just see the provider itself.
What is an MX record?
An MX (mail exchanger) record is a DNS entry that tells other mail servers where to deliver email for a domain. Each has a priority: senders try the lowest number first.
Why does it say the provider isn't recognised?
The domain may run its own mail server, or use a host we don't have a pattern for. The MX host names are still shown so you can search for them.
Why do I see a filtering service like Proofpoint or Mimecast?
Many companies route mail through a security gateway first. The MX records then point to the gateway, and the actual mailbox provider is hidden behind it. The SPF record often still names it.
Is the domain I look up sent to Volt Ghost?
No. Your browser asks Cloudflare's public DNS-over-HTTPS resolver (cloudflare-dns.com) directly. Volt Ghost's servers never see the query.