EmailKind
email classification, email API, developer tools, B2B lead qualification, email provider detection, company enrichment, MCP server, SaaS
About
EmailKind is an email classification API. Where verification tools tell you whether a mailbox exists, EmailKind tells you what kind of mailbox it is: which provider powers it, whether it belongs to a business or a person, and which company sits behind the domain.
One API call returns:
- Provider: the exact email service behind the domain, among 150+ providers (Google Workspace, Microsoft 365, Zoho, Fastmail, OVH, regional ESPs). EmailKind distinguishes providers that share the same MX servers, such as free Gmail vs paid Google Workspace.
- Type: business, personal, education, hosting, self-hosted or disposable, with boolean flags.
- Company: the organisation that owns a custom domain, resolved from SSL certificates, RDAP and website metadata, with no third-party enrichment tool.
- Confidence score: a certainty value on every result, so you decide what to automate and what to review.
- Normalized email: Gmail dot and +tag aliases collapsed into one canonical address.
- Role inboxes: shared addresses such as info@ or support@ flagged.
- Disposable: throwaway domains detected from a database updated daily.
Common use cases: qualifying B2B signups and routing only business emails to sales; auto-filling the company field in your CRM; adapting pricing or onboarding for Google Workspace vs Gmail users; segmenting your user base by email provider; analysing the composition of an existing list (share of business, personal and education addresses, top providers) through batch processing; and stopping free-trial abuse from disposable and role addresses.
How it works: EmailKind relies on passive DNS analysis only (MX and SPF records), matched against a database of 179,000+ classified domains updated daily. No SMTP probe, no email sent, no contact with mail servers. That makes it fast (sub-50ms response time, cached results) and privacy-friendly: the API processes domain-level data, runs on European infrastructure and is GDPR compliant.
Developer experience: a REST API with official SDKs for Python, Node.js and Go, and a five-minute setup. EmailKind is also MCP-native: its Model Context Protocol server (streamable HTTP) exposes classify and classify_batch tools, so Claude Desktop, Cursor, Windsurf and other AI agents can classify emails with no integration code, using the same API key and billing.
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