EmailKind

What It Does

EmailKind is an email classification API that identifies the exact email service provider, account type, and company behind any email address — without sending a single message. Unlike traditional email verification that pings mailboxes to check if they exist, EmailKind uses passive DNS analysis to determine whether an address is business or personal, which provider powers it (Google Workspace, Microsoft 365, Zoho, or 150+ others), and whether it's disposable or throwaway.

Who It's For & Problems Solved

EmailKind is built for SaaS platforms, B2B sales teams, CRM systems, and developers who need to qualify signups, prevent fraud, and enrich lead data at scale. It solves the critical problem of distinguishing high-intent business accounts from free-tier personal emails, blocking disposable addresses that abuse trials, and auto-filling company information without third-party enrichment tools. Whether you're routing qualified leads to sales, segmenting users by email provider, or preventing fake signups, EmailKind delivers actionable intelligence in under 50ms.

Key Features & Capabilities

• Provider Detection: Identify 150+ email providers including Google Workspace, Microsoft 365, Zoho, Fastmail, OVH, and regional ESPs. Distinguish shared-MX providers like Gmail vs Google Workspace.
• Type Classification: Categorize emails as business, personal, disposable, education, hosting, or self-hosted with confidence scores.
• Company Enrichment: Resolve custom domains to company names via SSL certificates, RDAP, and website metadata (e.g., [email protected] → Stripe, Inc.).
• Disposable Detection: Monitor 90,000+ disposable domains updated daily to block throwaway addresses.
• Batch Processing: Upload CSV files with up to 10,000 emails for bulk classification.
• MCP-Native: First email classification API with native Model Context Protocol support for Claude Desktop, Cursor, and Windsurf.
• Sub-50ms Response: Cached DNS results deliver near-instant responses with 99.9% uptime SLA.

Typical Workflows

Developers integrate EmailKind to qualify B2B signups by routing only is_business === true leads to sales, auto-fill CRM fields with company names, segment users by ESP for analytics, block disposable/role addresses at registration, dedupe Gmail aliases, and set confidence thresholds for automated approval workflows. The API processes domain-level data only — no personal identifiers, no SMTP probes.

Integrations & Developer Experience

Official SDKs available for Python (PyPI), Node.js (npm), and Go (pkg). RESTful API works with any HTTP client. Native MCP server enables zero-code integration with AI tools. Webhooks notify when domain classifications change. Enterprise features include custom rules, audit logs, and IP restrictions.

What Sets It Apart

EmailKind is the only email classification API combining provider detection, business/personal classification, disposable monitoring, and company enrichment in a single call. Its passive DNS approach avoids triggering spam alerts, and its continuously growing database (181,000+ domains classified daily) ensures expanding coverage. The MCP-native architecture makes it uniquely accessible to AI agents and developer tools without custom integration code.