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.

26 hosts · 322 ms

HostCertsFirst seenLast seenDNS
jira.coolblue.eu 2 2026-03-07 2026-07-23 ok
*.office.coolblue.eu 2 2025-07-07 2026-06-05 —
confluence.coolblue.eu 2 2025-09-03 2026-08-04 ok
realtime.coolblue.eu 3 2026-05-02 2026-08-20 ok
cryptshare.coolblue.eu 5 2026-05-13 2026-09-10 ok
collect-testing.coolblue.eu 4 2026-05-25 2026-09-14 ok
studiefabriek.coolblue.eu 1 2026-05-05 2026-05-05 ok
assetbank.coolblue.eu 2 2025-09-30 2026-08-30 ok
mail.coolblue.eu 2 2025-10-20 2026-09-20 ok
vpn.coolblue.eu 1 2026-05-05 2026-05-05 ok
www.vpn.coolblue.eu 1 2026-05-05 2026-05-05 nxdomain
sslvpn.coolblue.eu 1 2026-02-11 2026-02-11 ok
www.sslvpn.coolblue.eu 1 2026-02-11 2026-02-11 nxdomain
testvpn.coolblue.eu 1 2026-02-11 2026-02-11 ok
www.testvpn.coolblue.eu 1 2026-02-11 2026-02-11 nxdomain
extern.coolblue.eu 1 2026-02-10 2026-02-10 ok
www.extern.coolblue.eu 1 2026-02-10 2026-02-10 nxdomain
ellis.coolblue.eu 2 2025-07-05 2026-06-05 ok
myapps.coolblue.eu 2 2025-09-27 2026-08-28 ok
community.business.coolblue.eu 1 2025-11-04 2025-11-04 ok
auth.community.business.coolblue.eu 1 2025-11-04 2025-11-04 ok
workday.coolblue.eu 2 2025-06-10 2026-05-11 ok
sally.coolblue.eu 2 2026-03-18 2026-08-18 ok
delivery.coolblue.eu 2 2026-08-31 2026-08-31 ok
teamcity.coolblue.eu 2 2025-06-20 2026-05-19 ok
sally-api-proxy.coolblue.eu 2 2026-03-22 2026-08-22 ok

Programmatic access, with DNS A records: API GET /v1/hosts/coolblue.eu (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/coolblue.eu.