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.

19 hosts · 178 ms

HostCertsFirst seenLast seen
openkey.co 5 2026-05-31 2026-10-11
*.openkey.co 1 2025-11-12 2025-11-12
staging3.openkey.co 5 2026-06-05 2026-10-03
www.staging3.openkey.co 5 2026-06-05 2026-10-03
link.openkey.co 5 2026-05-02 2026-08-29
l.openkey.co 5 2026-05-02 2026-08-29
legal.openkey.co 5 2026-05-07 2026-09-04
webcheckin.openkey.co 2 2026-03-22 2026-08-22
integration.openkey.co 2 2025-10-09 2026-09-09
go.openkey.co 2 2026-03-25 2026-08-25
partners.openkey.co 3 2026-04-21 2026-09-21
status.openkey.co 5 2026-05-26 2026-09-22
get.openkey.co 4 2026-05-12 2026-09-04
*.dev.openkey.co 3 2026-04-15 2026-09-15
staffdev.openkey.co 1 2026-01-22 2026-01-22
integrationdev.openkey.co 2 2025-10-05 2026-09-05
hostdev.openkey.co 1 2026-01-22 2026-01-22
www.openkey.co 5 2026-05-31 2026-10-11
*.sandbox.openkey.co 1 2025-11-19 2025-11-19

Programmatic access: API GET /v1/hosts/openkey.co (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/openkey.co.