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.

26 hosts · 317 ms

HostCertsFirst seenLast seenDNS
calcoast.edu 39 2026-01-29 2026-09-20 ok
*.calcoast.edu 22 2026-01-29 2026-03-15 —
dev2.calcoast.edu 2 2026-02-09 2026-02-09 ok
beta.calcoast.edu 2 2026-07-01 2026-07-01 ok
*.beta.calcoast.edu 2 2026-07-01 2026-07-01 —
deac.calcoast.edu 2 2026-02-09 2026-02-09 ok
api-int-deac.calcoast.edu 2 2026-02-09 2026-02-09 ok
demo.calcoast.edu 4 2026-07-22 2026-09-19 ok
*.demo.calcoast.edu 4 2026-07-22 2026-09-19 —
api-app.calcoast.edu 1 2026-09-21 2026-09-21 nxdomain
secure-files.calcoast.edu 2 2026-09-18 2026-09-18 ok
*.secure-files.calcoast.edu 2 2026-09-18 2026-09-18 —
connect.calcoast.edu 6 2026-07-09 2026-09-06 ok
auth-connect.calcoast.edu 4 2026-09-16 2026-09-16 ok
*.connect.calcoast.edu 6 2026-07-09 2026-09-06 —
dev.calcoast.edu 13 2026-01-30 2026-09-19 ok
beta-dev.calcoast.edu 4 2026-07-06 2026-07-06 nxdomain
*.beta-dev.calcoast.edu 4 2026-07-06 2026-07-06 —
secure-files-dev.calcoast.edu 2 2026-09-17 2026-09-17 ok
*.secure-files-dev.calcoast.edu 2 2026-09-17 2026-09-17 —
api-int-dev.calcoast.edu 2 2026-02-09 2026-02-09 ok
apply-dev.calcoast.edu 2 2026-09-08 2026-09-08 ok
*.apply-dev.calcoast.edu 2 2026-09-08 2026-09-08 —
*.dev.calcoast.edu 12 2026-07-02 2026-09-19 —
apply.calcoast.edu 3 2026-09-20 2026-09-20 ok
*.apply.calcoast.edu 3 2026-09-20 2026-09-20 —

Programmatic access, with DNS A records: API GET /v1/hosts/calcoast.edu (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/calcoast.edu.