Find every subdomain
of a domain.

Every hostname under a domain that ever appeared in a public TLS certificate — with certificate counts and first/last seen dates.

6 hosts · 266 ms

HostCertsFirst seenLast seen
boldrpro.com 12 2026-06-05 2026-10-01
*.boldrpro.com 12 2026-06-05 2026-10-01
api.boldrpro.com 4 2026-04-26 2026-09-01
staging.api.boldrpro.com 4 2026-04-26 2026-10-07
app.boldrpro.com 6 2026-05-05 2026-09-17
staging.app.boldrpro.com 6 2026-04-23 2026-10-01

Programmatic access: API GET /v1/hosts/boldrpro.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/boldrpro.com.