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.

3 hosts · 312 ms

HostCertsFirst seenLast seen
fassbender-finanz.de 1 2025-12-01 2025-12-01
mta-sts.fassbender-finanz.de 5 2026-05-19 2026-09-17
www.fassbender-finanz.de 1 2025-12-01 2025-12-01

Programmatic access: API GET /v1/hosts/fassbender-finanz.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/fassbender-finanz.de.