Free tool
SSL certificate
The padlock in the address bar depends on a certificate that expires, has to cover the right names and must come with its full chain. We check all of that, plus where the http and www addresses lead.
What a certificate does
It proves to the browser that it is really talking to your site, and it encrypts everything exchanged: passwords, forms, payments. Without it, or if it has expired, browsers show a full-page warning that drives most visitors away.
The usual problems
01
Expired
Let's Encrypt certificates last 90 days and renew themselves… as long as the renewal works.
A DNS change or a moved site often breaks it.
02
Missing name
The certificate covers example.com but not www.example.com, or the reverse.
Both names should be in it.
03
Incomplete chain
The intermediate certificate was forgotten. Computers often cope; phones and email servers don't.
Install the “fullchain” file.
