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 · 276 ms

HostCertsFirst seenLast seen
skwws.de 3 2026-04-02 2026-09-18
mailing.skwws.de 5 2026-05-12 2026-09-08
www.skwws.de 3 2026-04-02 2026-09-18

Programmatic access: API GET /v1/hosts/skwws.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/skwws.de.