Is a Gmail address a business email?

No. An address ending in @gmail.com is a free, personal webmail account, even when a business owner uses it for work. A Google Workspace address on the company's own domain (jane@acme.com) is a business email, even though Google runs the mailbox. The rule that works in practice: classify by the domain after the @, not by who hosts the mail.

The same split applies to Microsoft and Yahoo. Short answers to the questions people ask next are below.

Which addresses count as personal?

Anything on a provider's consumer domain. The common ones:

This isn't the full list. pingutil's free-provider list has about 100 domains, and a few regional ones matter a lot depending on where your users are. Free email provider domains explains which ones are worth carrying and why the long lists online are mostly noise. Browse the current set on the free webmail category page.

Consumer ISP mailboxes (comcast.net, btinternet.com) are personal too, but they're a separate category because they behave differently: older users, rarely disposable, never a company.

Is a Google Workspace email a business email?

Yes. Workspace is Google's paid product for organisations, and it runs on a domain the organisation owns. The address looks like any company address: jane@acme.com. Nothing in the address says "Google".

If you need to confirm it, look at the domain's MX records. Google's setup guide tells new Workspace customers to publish a single MX record, smtp.google.com; older setups often use hosts starting with aspmx. Consumer gmail.com uses a different set (gmail-smtp-in.l.google.com and its alt hosts). You rarely need this check, though: the domain alone tells you it's not gmail.com.

Can a custom domain still be personal?

Yes, and this is where "business" gets fuzzy. Anyone can buy smithfamily.net and point it at Workspace or iCloud custom domains. Domain-based checks will call that a company domain. Two things help:

• Enrichment. If a lookup can't find any company behind the domain, or comes back with very low confidence, treat it as "custom domain, unknown owner" rather than as a lead.
• Context. A custom domain with a single signup and no website is different from one where five colleagues sign up in a week.

There's no perfect signal here. Plan for a "probably business" bucket rather than a yes/no.

How do I detect a Gmail or other personal address in code?

1. Split on the last @ and lowercase the host.
2. Reduce it to the registrable domain (mail.example.co.uk becomes example.co.uk).
3. Check it against a free-provider list and an ISP list. A match is personal.
4. Anything else is a candidate business domain. Optionally check MX and enrich it.

We walk through a full TypeScript version, with failure cases, in how to tell a business email from a personal one in code.

If you'd rather not maintain the lists, one API call returns the category:

curl -s -X POST https://pingutil.com/v1/lookup \
  -H "Authorization: Bearer $PINGUTIL_KEY" \
  -H "Content-Type: application/json" \
  -d '{ "input": "jane@gmail.com", "skip_enrichment": true }'

{ "domain": "gmail.com", "category": "free", "company": null,
  "verdict": { "is_spam": false, "low_trust": false, "reason": null } }

(Response trimmed.) category is free for webmail, isp for ISP mailboxes, company for everything that falls through the lists and TLD rules, plus educational, government and disposable. Drop skip_enrichment and a company domain also comes back with a company profile (name, industry, size estimate), generated by an LLM and cached per domain, so check its confidence field. Keep the key on your server and give the call a short timeout. Field details are in the API reference.

Note that free and verdict.is_spam answer different questions. A Gmail address is free and usually not spam. A machine-generated string like ccjxx90sze@gmail.com is free and is_spam: true because the local part looks random.

What should a B2B form do with a Gmail address?

Our opinion: don't hard-block it. Freelancers, consultants and very small companies often use Gmail for everything, and some of them are exactly the early customers you want. What tends to work:

• Ask, don't demand. Label the field "Work email" and, if someone enters a free address, show a gentle hint: "Using a work address helps us set up your team." Let them continue.
• Route instead of rejecting. Send free signups to self-serve onboarding and company signups to sales or a richer trial. Your SDRs spend time where there's a company to talk to.
• Hard-block only where the product needs a company, such as SSO setup or domain-verified team workspaces. Even then, say why.
• Treat disposable separately. A Gmail address is a real, long-lived inbox. A Mailinator address is not. Those deserve different rules.

The trade-offs (conversion, lead quality, what to measure) are in should your B2B signup form require a work email?.

Quick reference

• @gmail.com, @outlook.com, @hotmail.com, @yahoo.com: personal, free webmail.
• @yourcompany.com on Google Workspace or Microsoft 365: business.
• Custom domain with no company behind it: personal or unknown, flag it.
• Classify by registrable domain, keep a reason with the result, and don't block personal addresses unless the product truly requires a company.