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.

2 hosts · 186 ms

HostCertsFirst seenLast seen
netaid.or.jp 1 2025-12-26 2025-12-26
*.netaid.or.jp 1 2025-12-26 2025-12-26

Programmatic access: API GET /v1/hosts/netaid.or.jp (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/netaid.or.jp.