Last updated:
For announcements of upcoming changes, please see the API Announcements category on the Let’s Encrypt community forum.
Completed Features
ECDSA Root and Intermediates
- Enabled: June 06, 2024
We are issuing certificates from our production ECDSA intermediates to ECDSA leaf certificates. See the Chains of Trust documentation for full details on our PKI hierarchy.
ACME Renewal Information (ARI)
- Enabled: March 23, 2023
We now run ARI, a system that allows us to notify subscribers via API when they need to renew.
Multi-Perspective Validation
- Enabled: February 19, 2020
We now validate domain control from multiple network perspectives.
Certificate Transparency Log
- Enabled: May 15, 2019
We now operate a Certificate Transparency log.
TLS ALPN Challenge Support
- Enabled: July 12, 2018
We’ve specified and implemented a replacement for the TLS-SNI validation method, which was discontinued for security reasons. Introducing a replacement was important for subscribers who only want to use port 443 for validation.
Wildcard Certificates
- Enabled: March 13, 2018
ACME v2 API
- Enabled: March 13, 2018
Full IPv6 Support
- Enabled: July 26, 2016