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.

10 hosts · 278 ms

HostCertsFirst seenLast seenDNS
gsped.com 4 2026-04-12 2026-08-12 ok
*.gsped.com 2 2025-11-20 2025-11-20 —
doc.gsped.com 14 2026-04-07 2026-10-02 ok
staging.gsped.com 4 2026-04-12 2026-08-12 ok
mail.gsped.com 4 2026-04-12 2026-08-12 ok
netcomm.gsped.com 79 2026-04-09 2026-10-02 ok
apidocs.gsped.com 11 2026-06-02 2026-09-28 ok
sst.gsped.com 5 2026-05-24 2026-09-21 ok
load.sst.gsped.com 13 2026-04-09 2026-10-03 ok
www.gsped.com 4 2026-04-12 2026-08-12 ok

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