Three Kinds of Email Addresses
- Free webmail: addresses at providers such as Gmail, Outlook.com or Yahoo. Anyone can create one.
- Business (custom domain): addresses at a company’s own domain, such as
name@company.com. Usually tied to an organization. - Disposable: temporary inboxes created for a few minutes, often used to avoid giving a real address.
How to Check the Domain
1. Is It a Known Free Provider?
Our Free Email Test checks whether a domain belongs to a known free email provider. This is a list-based check, so it is fast and reliable for the large providers.
2. Can the Domain Receive Email?
A domain without MX records (and without an address to fall back on) cannot receive mail. Check with our DNS Record Lookup. See how to read MX records.
3. Who Hosts the Mail?
The MX hostnames reveal the mail provider. A company domain whose MX points to Google Workspace or Microsoft 365 is typical for real businesses.
4. Is It Disposable?
Disposable services constantly add new domains, so no list is complete. Signs include a very new domain (check the creation date with WHOIS Lookup) and MX records pointing to a known disposable mail service.
Using the Result Sensibly
- B2B lead forms: asking for a work email is reasonable, but rejecting all free addresses also rejects freelancers and small businesses that use Gmail. Consider flagging instead of blocking.
- Account sign-ups: blocking disposable addresses reduces abuse. Blocking free webmail usually hurts conversion.
- Always confirm ownership: no domain check proves that a person controls the address. Send a confirmation link.
What Domain Checks Cannot Tell You
A business domain can still belong to a one-person company, and a free address can belong to a large customer. Domain checks describe the address, not the person. Use them as one signal among others.
For Your Own Domain
If you send email from your own domain, make sure SPF, DKIM and DMARC are set up so your messages are trusted — see SPF, DKIM and DMARC explained.