Find every subdomain
of a domain.

Every hostname under a domain that ever appeared in a public TLS certificate — with certificate counts and first/last seen dates.

5 hosts · 241 ms

HostCertsFirst seenLast seen
mail.kbc.be 1 2025-12-08 2025-12-08
m.mail.kbc.be 1 2025-12-08 2025-12-08
res.mail.kbc.be 1 2025-12-08 2025-12-08
t.mail.kbc.be 1 2025-12-08 2025-12-08
www.mail.kbc.be 1 2025-12-08 2025-12-08

Programmatic access: API GET /v1/hosts/mail.kbc.be (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/mail.kbc.be.