Following our previous post on the foundational benefits of ACME Renewal Information (ARI), this one offers a detailed technical guide for incorporating ARI into existing ACME clients. Since its introduction in March 2023, ARI has significantly enhanced the resiliency and reliability of certificate revocation and renewal for a growing number of Subscribers....

On Thursday, June 6th, 2024, we will be switching issuance to use our new intermediate certificates. Simultaneously, we are removing the DST Root CA X3 cross-sign from our API, aligning with our strategy to shorten the Let’s Encrypt chain of trust. We will begin issuing ECDSA end-entity certificates from a default chain that just contains a single ECDSA...

On Wednesday, March 13, 2024, Let’s Encrypt generated 10 new Intermediate CA Key Pairs, and issued 15 new Intermediate CA Certificates containing the new public keys. These new intermediate certificates provide smaller and more efficient certificate chains to Let’s Encrypt Subscribers, enhancing the overall online experience in terms of speed, security,...

Let’s Encrypt is proud to introduce Sunlight, a new implementation of a Certificate Transparency log that we built from the ground up with modern Web PKI opportunities and constraints in mind. In partnership with Filippo Valsorda, who led the design and implementation, we incorporated feedback from the broader transparency logging community,...

This letter was originally published in our 2023 Annual Report. We typically open our annual report with a letter from our Executive Director and co-founder, Josh Aas, but he’s on parental leave so I’ll be filling in. I’ve run the Brand & Donor Development team at ISRG since 2016, so I’ve had the pleasure of watching our work mature,...

For more than ten years, we at the nonprofit Internet Security Research Group (ISRG) have been focused on our mission of building a more secure and privacy-respecting Internet for everyone, everywhere. As we touch on in our 2023 Annual Report, we now serve more than 360 million domains with free TLS certificates. Beyond being a big number, what does...