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SKULLCHECK TOOL

MTA-STS & TLS-RPT

Check SMTP transport-security policy discovery, HTTPS policy retrieval and TLS reporting.

Live check · No account required · Results depend on the DNS resolver and network access available to this hosting server.
ABOUT THIS TOOL

What MTA-STS and TLS-RPT protect

MTA-STS lets a domain publish transport-security expectations for inbound SMTP, while TLS-RPT provides a reporting channel for TLS delivery failures. This checker reviews the relevant DNS discovery records and, where supported, the HTTPS-hosted MTA-STS policy using outbound-request protections.