Certificate lifetime readiness · all certificates
What share of certificates worldwide have a validity window longer than the 47-day maximum being phased in?
86.32% of certificates worldwide (95% CI 85.99–86.64%), measured across 43,849 certificates on 2026-10-01.
Measured every Sunday since 2026-08-01 — 14 observations to date. Last measured 2026-10-01.
How this is measured
Read a Certificate Transparency log, parse each leaf, compute not_after − not_before. Entries are drawn as evenly spaced clusters across the 24 hours before the build, so every CA is represented in proportion to what it issued over the same period. Population unit: certificate; segmented by CA.
Built entirely from public bulk feeds — no target is contacted. Aggregate-only. 95% Wilson confidence intervals. Population: certificates newly issued and logged to Certificate Transparency, grouped by issuing CA. Snapshot: ct-window-24h-40000.
Licensed CC BY 4.0 — reuse with attribution to Quiet Failures. Download: JSON · CSV.
Why it matters
The same deadline seen from the supply side. It shows which CAs have already moved their customers to automated short-lived issuance and which are still writing certificates that will be non-compliant — a per-CA readiness table nobody else publishes.
Limits of this measurement
Measured over a sample of recent issuance, so it reflects current practice rather than the installed base. The 47-day threshold was chosen after a 100-day cut returned 0% everywhere — issuance had already moved below it, leaving no variance to observe. The sample is drawn in contiguous clusters rather than one certificate at a time, which widens the margin of error beyond what the sample size alone implies; the effect is small for a CA issuing steadily and largest for one that issues in bursts. A CA's figure covers only the sampled window, so a CA with low issuance in that window is suppressed rather than published thin. One further caveat on n, not on the rates: the sample is a fixed number of log entries however busy the log is, so the sampling fraction moves with the log's throughput — which halved between 2026-09-14 and 2026-09-27 (19.6M entries per 24h to 9.3M). Rates stay unbiased, but a segment's n tracks log volume as well as that issuer's own output, so week-to-week changes in n are not by themselves a change in issuance.