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.

4 hosts · 233 ms

HostCertsFirst seenLast seen
knowde.info 1 2025-12-07 2025-12-07
*.knowde.info 1 2025-12-07 2025-12-07
messaging.knowde.info 2 2026-04-02 2026-09-02
*.messaging.knowde.info 2 2026-04-02 2026-09-02

Programmatic access: API GET /v1/hosts/knowde.info (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/knowde.info.