Find every subdomain
of a domain.

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

6 hosts · 203 ms

HostCertsFirst seenLast seenDNS
finsom.ch 8 2026-04-23 2026-09-22 ok
*.finsom.ch 5 2026-04-23 2026-09-22 —
office.finsom.ch 5 2026-04-30 2026-09-15 ok
admin.finsom.ch 3 2026-06-13 2026-08-22 ok
connect.finsom.ch 5 2026-05-10 2026-09-24 ok
www.finsom.ch 3 2026-05-30 2026-08-08 ok

Programmatic access, with DNS A records: API GET /v1/hosts/finsom.ch (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/finsom.ch.