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.
Frequently asked questions
Is my SSL certificate still valid?
Enter the site address: the tool reads the certificate the server presents and shows its expiry date, its issuer and the names it covers. An expired certificate makes visitors see a warning screen.
Why did my Let's Encrypt certificate expire when it renews itself?
These certificates last 90 days and renew automatically as long as the renewal works. A DNS change, a moved site or a stopped scheduled task is enough to block it.
What does “incomplete chain” mean?
The intermediate certificate is not installed along with yours. Computers often cope, but Android and mail servers refuse the connection. Install the “fullchain” file supplied by the issuer.
