What is a Wildcard SSL certificate?

A Wildcard SSL certificate secures your website URL, and an unlimited number of its subdomains. A single Wildcard certificate can secure both www.coolexample.com, andblog.coolexample.com.

Wildcard certificates secure all of the subdomains at the level you specify when you submit your request. Just add an asterisk (*) in the subdomain area of the common name where you want to specify the wildcard. For example:

If you configure *.coolexample.com, you can secure
www.coolexample.com
photos.coolexample.com
blog.coolexample.com, etc.

If you configure *.www.coolexample.com, you can secure
mail.www.coolexample.com
photos.www.coolexample.com
blog.www.coolexample.com, etc.

Wildcard certificates secure websites the same as a regular SSL certificate, and requests are processed using the same validation methods. However, some Web servers might require a unique IP address for each subdomain on the Wildcard certificate.