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 · 218 ms

HostCertsFirst seenLast seenDNS
afis.co.jp 1 2025-07-23 2025-07-23 ok
secure-mail.afis.co.jp 1 2026-03-26 2026-03-26 ok
cms.afis.co.jp 1 2025-11-19 2025-11-19 ok
st.afis.co.jp 1 2025-11-19 2025-11-19 ok
www.afis.co.jp 2 2025-07-23 2026-07-07 ok

Programmatic access, with DNS A records: API GET /v1/hosts/afis.co.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/afis.co.jp.