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.

6 hosts · 231 ms

HostCertsFirst seenLast seen
ksk-saarlouis.de 6 2026-04-02 2026-09-18
psd2-xs2a.ksk-saarlouis.de 2 2025-08-06 2026-06-26
upload.ksk-saarlouis.de 1 2026-05-11 2026-05-11
module.ksk-saarlouis.de 6 2026-04-02 2026-09-18
mailing.ksk-saarlouis.de 6 2026-06-02 2026-09-29
www.ksk-saarlouis.de 6 2026-04-02 2026-09-18

Programmatic access: API GET /v1/hosts/ksk-saarlouis.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-saarlouis.de.