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.

14 hosts · 269 ms

HostCertsFirst seenLast seenDNS
gohappyhub.com 21 2026-05-12 2026-09-08 ok
*.gohappyhub.com 21 2026-05-12 2026-09-08 —
app-performance.gohappyhub.com 1 2026-09-29 2026-09-29 ok
app-staging.gohappyhub.com 2 2025-07-23 2026-06-23 ok
auth.gohappyhub.com 10 2026-04-30 2026-08-27 ok
email.jbhunt.mail.gohappyhub.com 2 2026-06-08 2026-06-08 nxdomain
email.gohappyhub.com 10 2026-04-18 2026-08-20 ok
roadmap.gohappyhub.com 6 2026-04-26 2026-08-30 ok
lp.gohappyhub.com 12 2026-04-18 2026-08-20 ok
help.gohappyhub.com 10 2026-05-29 2026-09-24 ok
app.gohappyhub.com 2 2025-07-17 2026-06-17 ok
ftp.gohappyhub.com 4 2026-07-01 2026-10-02 ok
resources.gohappyhub.com 10 2026-04-17 2026-08-20 ok
www.gohappyhub.com 8 2026-04-16 2026-08-20 ok

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