Working with Let's Encrypt's Short-Lived tlsserver and shortlived Profile Certificates

Let's Encrypt issues TLS certificates with a 90-day validity period by default. However, as the industry is gradually shortening TLS certificate lifetimes—with the maximum eventually expected to fall to 47 days—Let's Encrypt already offers certificates using the tlsserver profile with a validity period of 45 days. Compared with the current default classic profile, the tlsserver profile removes deprecated attributes such as the Common Name. Because it follows the latest recommended configuration, it also produces slightly smaller certificates. The differences between the profiles are documented on the following page. If you have already automated certificate issuance and renewal, it is worth considering an early move to the tlsserver profile. Certificate Profiles - Let's Encrypt Certificates issued with the classic profile are currently valid for 90 days. However, the validity period is scheduled to be shortened to 64 days in February 2027 and then to 45 days in February 2028. Certificate renewal automation is easy to leave untouched once it is working, and many monitoring systems also use fixed day-based thresholds. Both renewal automation and monitoring therefore require careful review. Decreasing Certificate Lifetimes to 45 Days - Let's Encrypt With only about six months remaining before the validity period is reduced to 64 days, now is a good time to begin validating your systems. Let's Encrypt also provides the shortlived profile for certificates that support IP addresses. These certificates are valid for only six days. With such a short lifetime, using them without automation is no longer practical. 6-Day and IP Address Certificates - Let's Encrypt To issue certificates using any of these profiles, you need an ACME client that supports ACME profile selection. Widely used clients such as Certbot should be able to issue them without difficulty. Issuing a certificate with the new tlsserver or shortlived profile is straightforward. The harder part is keeping it ren