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 · 339 ms

HostCertsFirst seenLast seenDNS
morphcast.com 12 2026-03-03 2026-09-24 ok
*.morphcast.com 6 2026-03-03 2026-07-21 —
origin.morphcast.com 5 2026-05-29 2026-09-24 ok
api-stage-origin.morphcast.com 4 2026-04-15 2026-08-14 ok
api-studio-origin.morphcast.com 6 2026-04-19 2026-08-19 ok
www.morphcast.com 6 2026-03-30 2026-09-24 ok

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