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.

6 hosts · 410 ms

HostCertsFirst seenLast seenDNS
osiweb.osinks.com 1 2025-09-24 2025-09-24 nxdomain
www.osiweb.osinks.com 1 2025-09-24 2025-09-24 nxdomain
mail.osinks.com 3 2025-08-14 2026-05-08 ok
www.mail.osinks.com 3 2025-08-14 2026-05-08 nxdomain
p.osinks.com 2 2025-06-25 2026-06-24 ok
www.p.osinks.com 2 2025-06-25 2026-06-24 nxdomain

Programmatic access, with DNS A records: API GET /v1/hosts/osinks.com (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/osinks.com.