Find every subdomain
of a domain.

Every hostname under a domain that ever appeared in a public TLS certificate — with certificate counts and first/last seen dates.

2 hosts · 230 ms

HostCertsFirst seenLast seen
em.ameriprise.com 5 2026-01-16 2026-09-13
*.em.ameriprise.com 3 2026-09-12 2026-09-13

Programmatic access: API GET /v1/hosts/em.ameriprise.com (API key for paging).

Shown here: hostnames with a certificate that is valid now or expired within the last 90 days. The full history since 2013 — hostnames whose last certificate expired earlier — is a Pro plan method: GET /v1/hosts-history/em.ameriprise.com.