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.

8 hosts · 260 ms

HostCertsFirst seenLast seen
sectionschool.com 8 2026-04-07 2026-10-08
*.sectionschool.com 3 2025-12-10 2026-09-07
demo.sectionschool.com 1 2025-12-10 2025-12-10
help.sectionschool.com 7 2026-05-20 2026-09-27
services.sectionschool.com 9 2025-12-16 2026-09-01
admin-services.sectionschool.com 9 2025-12-16 2026-09-01
gpt.sectionschool.com 10 2026-04-15 2026-10-09
www.sectionschool.com 10 2026-06-11 2026-10-07

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