Let's Encrypt

Let's Encrypt is a non-profit certificate authority run by the Internet Security Research Group (ISRG) that provides X.509 certificates for Transport Layer Security (TLS) encryption without charging fees. It is the world's largest certificate authority, used by more than 700 million websites, with the goal of creating a more secure and privacy-respecting web through the widespread adoption of HTTPS. The Internet Security Research Group, the provider of the service, is a public benefit organization. Major sponsors of the ISRG include the Electronic Frontier Foundation (EFF), the Mozilla Foundation, OVHcloud, Cisco Systems, Facebook, Google Chrome, the Internet Society, AWS, nginx, and the Gates Foundation. Other partners include the certificate authority IdenTrust, the University of Michigan, and the Linux Foundation.