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.

8 hosts · 385 ms

HostCertsFirst seenLast seenDNS
joycekoons.com 11 2026-05-20 2026-09-16 ok
*.joycekoons.com 11 2026-05-20 2026-09-16 —
database.joycekoons.com 1 2025-09-30 2025-09-30 nodata
www.database.joycekoons.com 1 2025-09-30 2025-09-30 nxdomain
central.joycekoons.com 3 2026-03-24 2026-07-18 ok
mta-sts.joycekoons.com 3 2026-04-23 2026-09-12 ok
dev.joycekoons.com 2 2026-04-12 2026-08-04 ok
www.joycekoons.com 5 2026-05-21 2026-09-19 ok

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