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.

6 hosts · 301 ms

HostCertsFirst seenLast seenDNS
stimulus.com 9 2026-04-15 2026-09-19 ok
*.stimulus.com 9 2026-04-15 2026-09-19 —
beta.stimulus.com 3 2026-05-21 2026-09-08 ok
auth.stimulus.com 4 2026-04-21 2026-08-19 ok
cdn.stimulus.com 3 2026-05-20 2026-09-06 ok
www.stimulus.com 3 2026-05-21 2026-09-08 ok

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