MTA-STS Check with a clear result

For web teams checking a launch or tracing a fault, this test provides an immediate point of reference. Inspect the MTA-STS policy that secures inbound email over TLS.

Inspect the MTA-STS policy that secures inbound email over TLS. The result organizes the useful evidence so you can focus the diagnosis.

How to use

Enter the mail domain you want to inspect in the field, without adding a protocol or a path.
Run the test so the policy lookup can be performed for that domain.
Read the returned result, which gathers the DNS and policy details available publicly.
Compare the displayed settings with the values expected by your email provider.
Run the check again after a DNS change to follow how the update propagates.

Example

A mail administrator is preparing a provider migration and wants to know whether the domain already advertises an MTA-STS policy. They enter the domain, launch the test and review the returned details before changing any DNS records.

Limits and formats

The result depends on publicly visible DNS data at the time of the test, so an ongoing propagation can make the reading incomplete.
The check does not configure anything for you and is not a full deliverability or email security audit.
A typo in the domain, or a domain without a published policy, can lead to an empty or partial answer.
Confirm the policy dates and their consistency with your MX hosts before you treat the result as final.

Where processing happens

Your input is sent to the YOORfree server, which then queries public DNS and the target site to retrieve the MTA-STS policy. No file is uploaded. The answer comes back into the page and reflects what was publicly available when the check ran.

Frequently asked questions

What does an MTA-STS check look for?

It looks for the policy published for the domain and the DNS details that let mail servers enforce TLS strictly. The result helps you see whether a policy exists and whether the public information appears consistent.

Why might the result differ between two runs?

DNS records and the published policy can be edited or cached. After you make a change, wait for propagation and run the check again so you can compare the new answer with the previous one.

Should I include a web prefix or a page path?

No. Enter only the domain name used for email. A web prefix or a page path does not help this lookup and may prevent the check from finding the policy.