MTA-STS + TLS-RPT

Mail Transport Security Analyzer

Check whether a domain publishes transport-security policy and reporting, then verify the standard MTA-STS policy endpoint when safe to do so.

mta-sts checkertls-rpt checkeremail tls checkersmtp tls policy
Audit SMTP transport policyChecks MTA-STS and TLS-RPT using their standard public locations.

What this analysis does

The analyzer combines the _mta-sts policy identifier, the HTTPS policy file and the _smtp._tls reporting record into one transport-security view.

How to use the result

Use real evidence

Paste the exact domain, header, message or configuration. The result is only as useful as the evidence supplied.

Review the findings

Mailybox separates observations from inferred causes so you can see what is known and what still needs verification.

Retest after changes

Email authentication and routing are stateful. Re-run the analysis after publishing a fix.

Interpretation matters

Email systems combine DNS, message-level evidence, provider policy and intermediate infrastructure. A single passing check is not proof that every message will deliver, and a single warning is not proof that a domain is misconfigured. Mailybox is designed to expose the evidence and the relationship between signals so the next action is clear.