Klaviyo vs Substack

Klaviyo is used by more websites in our catalog: 13,451 use Klaviyo and 1,089 use Substack.

Substack sites have the higher median Ahrefs Domain Rating (Klaviyo: 32, Substack: 33).

Between 2026-06 and 2026-07, Klaviyo went from 2.0% to 1.5% of all tracked sites, while Substack went from 0.16% to 0.12%. Substack is gaining ground faster in our index.

No. A site runs a single email / newsletter platform, so Klaviyo and Substack 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.