API archive entry · source-reported
Email Validation
Validate email addresses for deliverability and spam
Other Email APIs
These records share a directory category and are ordered by similarity of reported access facts. They are a shortlist, not proof of drop-in compatibility.
Cloudmersive Validate
Validate email addresses, phone numbers, VAT numbers and domain names
API key · HTTPS reported · CORS Yes
EmailJS
Send emails directly from client-side JavaScript without a backend server
API key · HTTPS reported · CORS Yes
Kiprio Email Validate
Free email validation: MX check, disposable detection, syntax
API key · HTTPS reported · CORS Yes
SMTPfast
Send transactional email, manage contacts and broadcasts, free 3,000 emails/month
API key · HTTPS reported · CORS Yes
Verifier
Verifies that a given email is real
API key · HTTPS reported · CORS Yes
Atomic Mail
Email for AI agents: programmatic inbox creation and send/receive over JMAP
API key · HTTPS reported · CORS Unknown
How to compare them
Coverage
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Operating cost
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Integration risk
Test auth, errors, pagination, latency, versioning, and outage behavior.
Data rights
Review attribution, redistribution, retention, privacy, and commercial-use terms.
Source reference
This page separates source-reported facts from questions that need live provider verification.