Unverified50% confidenceFactExact time
Email domain deliverability checks typically include syntax validation (RFC 5322), DNS MX record lookup, and optional SMTP probing.
1
Sources
50%
Confidence
Long-term
Relevance
10/27/2026
First Seen
Sources
Related Entities
Related Claims
UnverifiedEmail verification checks whether an address actually exists via SMTP handshake or DNS record lookup, thereby filtering out invalid addresses before sending and reducing bounce rates.77% similarUnverifiedReachability scoring can be implemented through automated methods such as HTTP status code detection, regex email format validation, and MX record lookup.74% similarUnverifiedThe author built an email deliverability check API that in one call returns SPF/DKIM/DMARC/MX/rDNS verdicts for a domain, along with remediation tips.74% similarUnverifiedDNS queries have caching and timeout issues, and SMTP probing may be rate-limited or rejected by the target server, so email domain validation results are not absolutely stable.70% similarUnverifiedRFC 5321是IETF制定的SMTP标准，规定邮箱地址local-part的解释权归属于接收方邮件服务器70% similar
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