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.

19 hosts · 231 ms

HostCertsFirst seenLast seen
hypnozio.com 24 2026-05-01 2026-09-28
*.hypnozio.com 14 2026-05-01 2026-09-28
27065001.hypnozio.com 8 2026-05-25 2026-09-20
links1.hypnozio.com 5 2026-05-25 2026-09-22
payments2.hypnozio.com 8 2026-05-25 2026-09-20
click.update.hypnozio.com 6 2026-06-30 2026-08-28
bounces.update.hypnozio.com 6 2026-06-30 2026-08-28
images.update.hypnozio.com 10 2026-05-25 2026-09-20
staging.hypnozio.com 11 2026-05-25 2026-09-20
mail.hypnozio.com 9 2026-05-25 2026-09-20
click.info.hypnozio.com 6 2026-06-30 2026-08-28
bounces.info.hypnozio.com 4 2026-06-30 2026-08-28
images.info.hypnozio.com 8 2026-05-25 2026-09-20
tracktor.hypnozio.com 8 2026-05-25 2026-09-20
itlinks.hypnozio.com 9 2026-05-25 2026-09-20
payments.hypnozio.com 10 2026-05-25 2026-09-20
mta-sts.hypnozio.com 6 2026-06-19 2026-08-17
support.hypnozio.com 14 2026-05-19 2026-09-14
www.hypnozio.com 12 2026-05-25 2026-09-20

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