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 · 212 ms

HostCertsFirst seenLast seen
plantformance.com 17 2026-01-16 2026-09-27
*.plantformance.com 3 2026-08-28 2026-08-31
webauth.plantformance.com 1 2026-08-28 2026-08-28
docs.plantformance.com 4 2026-08-19 2026-08-20
mgt.plantformance.com 1 2025-11-19 2025-11-19
www.mgt.plantformance.com 1 2025-11-19 2025-11-19
memberstack-client.plantformance.com 1 2026-08-21 2026-08-21
www.plantformance.com 12 2026-01-16 2026-09-27

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