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.

7 hosts · 163 ms

HostCertsFirst seenLast seen
qa.researchsignals.spglobal.com 2 2026-03-04 2026-07-20
qa-alb.qa.researchsignals.spglobal.com 2 2026-03-04 2026-07-20
vradbsite.qa.researchsignals.spglobal.com 2 2026-03-04 2026-07-20
api.qa.researchsignals.spglobal.com 3 2025-12-09 2026-07-20
*.api.qa.researchsignals.spglobal.com 1 2025-12-09 2025-12-09
signalsmailer.qa.researchsignals.spglobal.com 2 2026-03-04 2026-07-20
rabbit.qa.researchsignals.spglobal.com 2 2026-03-04 2026-07-20

Programmatic access: API GET /v1/hosts/qa.researchsignals.spglobal.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/qa.researchsignals.spglobal.com.