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.

17 hosts · 377 ms

HostCertsFirst seenLast seenDNS
katalys.com 23 2026-05-21 2026-09-19 ok
*.katalys.com 24 2025-09-22 2026-09-19 —
kb.katalys.com 1 2025-12-10 2025-12-10 ok
staging.katalys.com 5 2026-04-23 2026-09-20 ok
*.staging.katalys.com 5 2025-07-25 2026-08-21 —
chat.staging.katalys.com 5 2026-05-12 2026-09-13 ok
*.dev-branch.katalys.com 1 2025-12-17 2025-12-17 —
track.katalys.com 7 2025-09-27 2026-08-30 ok
payments.katalys.com 3 2026-05-27 2026-08-04 ok
mta-sts.katalys.com 5 2026-06-03 2026-10-01 ok
status.katalys.com 4 2026-04-16 2026-08-14 ok
chat.katalys.com 5 2026-05-14 2026-09-16 ok
*.dev.katalys.com 4 2025-07-25 2026-07-05 —
ops.dev.katalys.com 5 2026-04-22 2026-08-26 ok
chat.dev.katalys.com 5 2026-05-12 2026-09-14 ok
grow.katalys.com 6 2026-05-31 2026-10-02 ok
www.katalys.com 3 2026-05-25 2026-08-09 ok

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