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 · 228 ms

HostCertsFirst seenLast seenDNS
kskmayen.de 5 2026-04-02 2026-09-18 ok
psd2-xs2a.kskmayen.de 1 2026-05-21 2026-05-21 nxdomain
module.kskmayen.de 5 2026-04-02 2026-09-18 ok
mailing.kskmayen.de 5 2026-05-10 2026-09-07 ok
www.kskmayen.de 5 2026-04-02 2026-09-18 ok

Programmatic access, with DNS A records: API GET /v1/hosts/kskmayen.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/kskmayen.de.