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.

8 hosts · 293 ms

HostCertsFirst seenLast seenDNS
jaspr.co 22 2026-04-17 2026-09-28 ok
*.jaspr.co 7 2026-05-29 2026-09-24 —
ca.jaspr.co 14 2026-04-16 2026-09-30 ok
join.jaspr.co 4 2026-04-19 2026-08-24 ok
onair.jaspr.co 13 2026-04-17 2026-09-28 ok
partners.jaspr.co 4 2026-04-20 2026-08-24 ok
account.jaspr.co 15 2026-05-12 2026-09-22 ok
www.jaspr.co 4 2026-04-16 2026-08-13 ok

Programmatic access, with DNS A records: API GET /v1/hosts/jaspr.co (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/jaspr.co.