How to use telnet to test ssl/https websites

As I wrote recently, I had some issues with SSL on one of my sites. As part of the troubleshooting process I wanted a way to confirm that the site was responding properly on port 443 (the secure default SSL port) and that the SSL certificate was being presented properly.

The solution I used was to open a terminal session (or use a telnet program) from my Mac and leverage openssl (which was already there – nothing to install) to test the site.

Here’s the command I used…

openssl s_client -connect YourDomain.com:443

If SSL is working on your site you’ll see the actual certificate scroll by in the window (you know, all that crazy hex stuff) and it will confirm an “SSL handshake” took place.

Hope that helps!