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.

4 hosts · 218 ms

HostCertsFirst seenLast seen
leaderssl.de 1 2026-01-30 2026-01-30
digicert.leaderssl.de 5 2026-04-25 2026-08-23
www.digicert.leaderssl.de 10 2026-04-25 2026-08-23
www.leaderssl.de 3 2025-10-14 2026-01-30

Programmatic access: API GET /v1/hosts/leaderssl.de (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/leaderssl.de.