Free SMTP TLS Checker

Check STARTTLS support, TLS handshake, and certificate validity for your mail server.

Checking DNS records…

Related MXFend tools
MTA-STS Checker Validate your MTA-STS DNS and HTTPS policy. TLS-RPT Checker Validate your TLS reporting DNS record. Email Security Score Complete domain report for authentication, reputation, and transport security.
MXFend

Free email deliverability tools for domains.

Tools
Email Deliverability Checker SPF Checker DMARC Checker MX Checker
Guides
Email auth guide Emails going to spam Domain reputation SMTP TLS MTA-STS TLS-RPT
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