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 · 212 ms

HostCertsFirst seenLast seenDNS
governforcalifornia.org 12 2026-04-24 2026-09-18 ok
*.governforcalifornia.org 6 2026-05-21 2026-09-18 —
donate.governforcalifornia.org 1 2026-01-05 2026-01-05 ok
donate-staging.governforcalifornia.org 2 2025-08-20 2026-07-21 ok
action.governforcalifornia.org 1 2026-01-12 2026-01-12 ok
www.governforcalifornia.org 5 2026-04-24 2026-08-27 ok

Programmatic access, with DNS A records: API GET /v1/hosts/governforcalifornia.org (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/governforcalifornia.org.