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.

9 hosts · 286 ms

HostCertsFirst seenLast seenDNS
hyperithm.com 13 2026-04-13 2026-09-23 ok
*.hyperithm.com 6 2026-04-13 2026-09-23 —
pnl2.hyperithm.com 2 2025-09-18 2025-10-16 nxdomain
accountable.hyperithm.com 1 2025-12-16 2025-12-16 ok
tech.hyperithm.com 4 2026-05-31 2026-08-02 ok
pnl.hyperithm.com 1 2025-12-11 2025-12-11 ok
cam.hyperithm.com 5 2026-05-22 2026-09-22 ok
vaults.hyperithm.com 4 2026-04-09 2026-08-07 ok
www.hyperithm.com 8 2026-05-05 2026-08-31 ok

Programmatic access, with DNS A records: API GET /v1/hosts/hyperithm.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/hyperithm.com.