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 · 266 ms

HostCertsFirst seenLast seenDNS
ksk-schluechtern.de 3 2026-04-20 2026-05-07 ok
psd2-xs2a.ksk-schluechtern.de 3 2025-08-29 2026-08-13 nxdomain
module.ksk-schluechtern.de 2 2026-05-07 2026-05-07 ok
mailing.ksk-schluechtern.de 5 2026-05-01 2026-08-29 ok
www.ksk-schluechtern.de 3 2026-04-20 2026-05-07 ok

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