MailRook

MailRook provides email validation and enrichment tools for businesses, marketers, sales teams, and developers. Its services help verify addresses, reduce email bounces, identify disposable or risky signups, and assess domain credibility. Users can check individual addresses through a free online email checker, upload lists for cleaning, or integrate validation into their systems using a real-time REST API. The site also offers an MCP server for AI agents, API documentation, and free utilities for checking syntax, disposable addresses, domains, catch-all behavior, SPF and DMARC records, and mail servers.

MailRook’s checks cover mailbox and SMTP status, role-based and catch-all addresses, provider information, domain age and infrastructure, and potential fraud signals. Its domain enrichment features provide company and technical details, while gateway detection identifies services such as Proofpoint, Mimecast, and Barracuda. Results include deliverability and trust scores with reasons to help teams decide whether to allow, challenge, suppress, or contact an address. The service advertises 25 free checks per day without a credit card, GDPR compliance, 99.9% uptime, and a median check time under 500 milliseconds.