Secure
The site answers over HTTPS and sends an HSTS header.
Free HTTPS lookup for any website
Check how a site answers over HTTPS: the status, any redirects, how long it takes and its security headers.
- Free, with no signup
- Saves nothing it checks
What your result means
With warnings
The site answers, but it sends no HSTS header or returns a client error.
No answer
The site did not answer over HTTPS, its certificate failed, or it returned a server error.
Questions about the HTTPS lookup
What is HSTS?
A header that tells browsers to use only HTTPS for the site for a set time, so they never fall back to plain HTTP.
Should a sending domain redirect to my main site?
Many senders point their sending domains at the main site, so a recipient who types the domain lands somewhere real.
Why does the check fail when my browser loads the site?
Your browser may have the page cached, or the site may block requests from data centers. The check asks from a cloud network.
Found a problem? We will check the rest.
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