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.

11 hosts · 368 ms

HostCertsFirst seenLast seenDNS
cytena.com 20 2026-04-22 2026-08-25 ok
testimonial.cytena.com 4 2026-05-27 2026-07-25 ok
licensing-portal.cytena.com 1 2026-02-23 2026-02-23 ok
lifesciences.cytena.com 14 2026-04-09 2026-10-03 ok
files.cytena.com 14 2026-05-29 2026-09-24 ok
notifications.cytena.com 6 2026-05-28 2026-09-24 ok
meet.cytena.com 9 2026-05-29 2026-09-24 ok
sst.cytena.com 5 2026-04-24 2026-08-22 ok
load.sst.cytena.com 8 2026-04-24 2026-08-20 ok
www.cytena.com 14 2026-04-22 2026-08-25 ok
testx.cytena.com 5 2026-08-17 2026-08-17 ok

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