Find every subdomain
of a domain.

Every hostname under a domain that ever appeared in a public TLS certificate — with certificate counts, first/last seen and live DNS status.

16 hosts · 292 ms

HostCertsFirst seenLast seenDNS
test.studentaid.gov 3 2025-09-10 2026-09-23 nodata
*.test.studentaid.gov 48 2026-04-14 2026-08-20 —
track.test.studentaid.gov 5 2025-10-15 2026-09-25 ok
portal.test.studentaid.gov 5 2025-10-15 2026-09-25 ok
*.mail.test.studentaid.gov 12 2026-04-17 2026-08-20 —
*.origin.test.studentaid.gov 20 2026-04-14 2026-08-20 —
*.apps.hcp.test.studentaid.gov 2 2026-09-18 2026-09-21 —
console-openshift-console.apps.hcp.test.studentaid.gov 1 2026-09-21 2026-09-21 nodata
oauth-openshift.apps.hcp.test.studentaid.gov 2 2026-09-18 2026-09-21 nodata
*.apps.temp.test.studentaid.gov 5 2026-04-13 2026-09-09 —
console-openshift-console.apps.temp.test.studentaid.gov 5 2026-04-13 2026-09-09 nodata
oauth-openshift.apps.temp.test.studentaid.gov 5 2026-04-13 2026-09-09 nodata
docs.test.studentaid.gov 5 2025-10-15 2026-09-25 ok
*.apps.test.studentaid.gov 1 2026-09-09 2026-09-09 —
console-openshift-console.apps.test.studentaid.gov 2 2026-09-09 2026-09-09 nodata
oauth-openshift.apps.test.studentaid.gov 1 2026-09-09 2026-09-09 nodata

Programmatic access, with DNS A records: API GET /v1/hosts/test.studentaid.gov (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/test.studentaid.gov.