Browser tool

Lifetime calendar

Public TLS certificates are getting shorter in steps. Start from how often you renew, or from a certificate, and see when each step reaches you and how many renewals a year it means.

Lifetime calendar

Runs in your browser. Nothing you type or paste is sent anywhere.

Start from

The schedule for public TLS certificates

Issued fromLongest lifetimeDomain check reuseRenewals a year, at least
1 September 2020398 days398 days (from 1 October 2021)1
15 March 2026200 days200 days2
15 March 2027100 days100 days4
15 March 202947 days10 days8

From the CA/Browser Forum Baseline Requirements (sections 6.3.2 and 4.2.1), checked 20 October 2026. Renewals a year: 365 divided by the lifetime, rounded up; renewing earlier means more.

How to use it

  1. Choose how to start: how often you renew today, a certificate you paste, or its two dates.
  2. Add how many certificates you look after, to see the yearly total.
  3. Read when each step affects you, then the schedule and your renewals per year.

Questions

Where do the limits come from?

From the CA/Browser Forum Baseline Requirements, which public CAs must follow. The tool reads the numbers and dates from this site's checked list of dated facts.

Do the limits apply to my private CA?

No. They apply to publicly trusted TLS certificates. A private CA sets its own lifetimes, although short lifetimes and automation are good practice there too.

How do I keep up with renewals?

Automate them with ACME, the protocol most public CAs support, and monitor expiry dates. The handbook chapter on ACME shows how.