HTTPfy

Let's Encrypt certificates on popular websites

Let's Encrypt issued 1835 of the 8,208 certificates we observed on popular sites in November 2026.

22.4%of observed certificates1835 of 8,208
90 daysmedian validity period
5.1%expiring within 30 daysat scan time
98.1%validated for the host name

Validity period

Days between notBefore and notAfter of the leaf certificate.

up to 100 days 100.0%
101 to 200 days 0.0%
201 to 398 days 0.0%
over 398 days 0.0%

TLS versions negotiated

On sites using Let's Encrypt (accent) and all sites (grey).

TLSv1.3 91.8%
all sites 84.9%
TLSv1.2 8.2%
all sites 15.1%

About Let's Encrypt

Issuer organisation names seen in these certificates: Let's Encrypt (1835).

Let's Encrypt issues certificates through the ACME protocol, so they are usually renewed automatically by a client such as Certbot, which explains short validity periods.

21.0% of the domains using Let's Encrypt publish a CAA record (all sites: 20.7%). A CAA record names the CAs allowed to issue for the domain; any other CA must refuse.

3 certificates from Let's Encrypt had already expired when we checked.

CA site: https://letsencrypt.org/

Popular sites with a Let's Encrypt certificate

twitter.commail.ruwikipedia.orgx.comcloudflare.networdpress.orgntp.orgnginx.orgwordpress.comt-online.delencr.orgnginx.com

Check one yourself:

Source: our own scan of November 2026 (2026-11-11), 9,971 of the top 10,000 domains of the Tranco list Y895G that answered in DNS. Method and data.