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.

5 hosts · 270 ms

HostCertsFirst seenLast seenDNS
ibb-woern.de 6 2026-06-02 2026-09-30 ok
baustellenberichte.ibb-woern.de 5 2026-05-05 2026-09-02 ok
projektverwaltung.ibb-woern.de 4 2026-06-09 2026-10-07 ok
bimi.ibb-woern.de 4 2026-04-19 2026-08-17 ok
www.ibb-woern.de 4 2026-04-11 2026-08-09 ok

Programmatic access, with DNS A records: API GET /v1/hosts/ibb-woern.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/ibb-woern.de.