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 · 276 ms

HostCertsFirst seenLast seenDNS
3dsecureint2.csast.cz 2 2026-05-30 2026-06-18 ok
3dsecurepred.csast.cz 2 2026-05-30 2026-06-18 ok
jamfcloud.csast.cz 1 2026-01-20 2026-01-20 ok
pred-be.webapi.csast.cz 2 2026-08-26 2026-08-26 nxdomain
prs-be.webapi.csast.cz 1 2026-04-14 2026-04-14 ok
sys-be.webapi.csast.cz 2 2026-08-26 2026-08-26 nxdomain
int-be.webapi.csast.cz 1 2026-04-14 2026-04-14 ok
portal.csast.cz 1 2026-01-13 2026-01-13 nxdomain
enterpriseregistration.csast.cz 1 2025-06-12 2025-06-12 ok
filesender.csast.cz 1 2026-04-20 2026-04-20 nxdomain
3dsecureprs.csast.cz 2 2026-05-30 2026-06-18 ok
3dsecureint.csast.cz 2 2026-05-30 2026-06-18 ok
enterpriseregistration.ext.csast.cz 1 2025-06-12 2025-06-12 ok
3dsecuredev.csast.cz 2 2026-05-30 2026-06-18 ok

Programmatic access, with DNS A records: API GET /v1/hosts/csast.cz (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/csast.cz.