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.

27 hosts · 310 ms

HostCertsFirst seenLast seenDNS
alcosan.org 12 2025-07-18 2026-08-26 ok
gisprod.alcosan.org 1 2026-05-30 2026-05-30 ok
www.gisprod.alcosan.org 1 2026-05-30 2026-05-30 ok
ucedge.alcosan.org 4 2025-10-04 2026-07-03 ok
www.ucedge.alcosan.org 4 2025-10-04 2026-07-03 nxdomain
exchange.alcosan.org 6 2025-07-18 2026-08-26 ok
www.exchange.alcosan.org 6 2025-07-18 2026-08-26 nxdomain
municipal.alcosan.org 7 2025-08-03 2026-09-04 ok
www.municipal.alcosan.org 4 2025-08-03 2026-08-31 nxdomain
portal.alcosan.org 5 2025-09-19 2026-09-30 ok
www.portal.alcosan.org 5 2025-09-19 2026-09-30 nxdomain
mail.alcosan.org 6 2025-07-18 2026-08-26 ok
webmail.alcosan.org 6 2025-07-18 2026-08-26 ok
securemail.alcosan.org 3 2026-03-24 2026-05-22 ok
www.securemail.alcosan.org 3 2026-03-24 2026-05-22 nxdomain
vpn.alcosan.org 2 2025-10-05 2025-11-01 ok
www.vpn.alcosan.org 2 2025-10-05 2025-11-01 nxdomain
autodiscover.alcosan.org 6 2025-07-18 2026-08-26 ok
maps.alcosan.org 13 2026-07-24 2026-08-04 ok
www.maps.alcosan.org 13 2026-07-24 2026-08-04 nxdomain
careers.alcosan.org 5 2025-06-06 2026-09-09 ok
www.careers.alcosan.org 5 2025-06-06 2026-09-09 nxdomain
gisdev.alcosan.org 1 2026-05-30 2026-05-30 ok
www.gisdev.alcosan.org 1 2026-05-30 2026-05-30 nxdomain
priv.alcosan.org 2 2025-10-10 2025-11-01 ok
www.priv.alcosan.org 2 2025-10-10 2025-11-01 nxdomain
www.alcosan.org 3 2025-08-28 2026-09-04 ok

Programmatic access, with DNS A records: API GET /v1/hosts/alcosan.org (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/alcosan.org.