Let’s Encrypt is a free, automated, and open Certificate Authority. They issue free certificates with server validation features.
A good way to get started is to use https://gethttpsforfree.com/, which is a website that will take you through the manual steps to get your free https certificate so you can make your own website use https!
It requires you server a special string under your server at the domain that you requested. Fairly a simple way to get a free certificate every 3 months.
Let’s Encrypt! are a 501(c)(3) nonprofit. They’re running a crowdfunding campaign to support their operations, please consider contributing now!