FREE EMAIL SECURITY TOOL
MTA-STS Checker
Check MTA-STS DNS signaling, HTTPS policy retrieval, mode, maximum age and MX coverage.
Enter a domain to inspect its MTA-STS transport-security policy.
ABOUT THIS CHECK
What does MTA-STS protect?
MTA-STS lets receiving domains publish a policy that tells supporting senders how TLS should be used when delivering mail to their MX servers.