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 · 242 ms

HostCertsFirst seenLast seen
oscarwylee.com 8 2025-08-29 2026-10-07
*.oscarwylee.com 9 2025-08-29 2026-10-07
lab.oscarwylee.com 10 2026-05-26 2026-09-25
notifications.oscarwylee.com 5 2026-05-24 2026-09-21

Programmatic access: API GET /v1/hosts/oscarwylee.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/oscarwylee.com.