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.

4 hosts · 248 ms

HostCertsFirst seenLast seen
msg.tw.sc.com 1 2025-12-15 2025-12-15
m2.msg.tw.sc.com 1 2025-12-15 2025-12-15
res2.msg.tw.sc.com 1 2025-12-15 2025-12-15
t2.msg.tw.sc.com 1 2025-12-15 2025-12-15

Programmatic access: API GET /v1/hosts/msg.tw.sc.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/msg.tw.sc.com.