Open-source email verification API.
Reacher is an open-source email-verification API for checking deliverability, cleaning lists, and preventing bounces. It supports individual and bulk checks, self-hosting, and a hosted API.
Reacher provides an SMTP-based verification engine. Its docs describe a dashboard and API workflow, with results classified as safe, invalid, risky, or unknown.
Teams and developers that need email-list verification or deliverability checks and can use an API or self-hosted service.
Teams seeking a broad sales-engagement or CRM platform should look elsewhere: the confirmed material is narrowly about email verification.
No curated rival set covers this tool yet, so these are simply other tools in the same architectural layer and product form. Treat it as a starting point, not a shortlist.
Its documentation describes checks for deliverability, including mailbox existence, MX records, disposable providers, and catch-all domains.
Yes. The documentation includes installation, scaling, licensing, proxy, and configuration guides for self-hosting.
Yes. The docs state that the API supports individual checks and bulk verification processes.
This page tells you whether Reacher fits. Cheetah builds and runs the system it goes into — enrichment, sequencing, CRM and the joins between them.
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