Let's Encrypt vs ZeroSSL

Let's Encrypt is used by more websites in our catalog: 466,882 use Let's Encrypt and 2,425 use ZeroSSL.

Let's Encrypt and ZeroSSL sites have a similar median Ahrefs Domain Rating.

Between 2026-06 and 2026-07, Let's Encrypt went from 59% to 53% of all tracked sites, while ZeroSSL went from 0.29% to 0.28%. ZeroSSL is gaining ground faster in our index.

No. A site runs a single SSL certificate authority, so Let's Encrypt and ZeroSSL are mutually exclusive.

Adoption is counted from Site Stats Database's own crawl; Domain Rating comes from Ahrefs and traffic from DataForSEO. Figures reflect the sites we track and refresh at least monthly.