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.

9 hosts · 262 ms

HostCertsFirst seenLast seen
nu.co 17 2026-04-30 2026-09-30
*.nu.co 2 2026-04-30 2026-09-30
*.global.nu.co 2 2026-04-30 2026-09-30
news.global.nu.co 2 2026-04-30 2026-09-30
*.news.global.nu.co 2 2026-04-30 2026-09-30
dam.nu.co 1 2025-11-11 2025-11-11
*.us.nu.co 2 2026-04-30 2026-09-30
*.news.us.nu.co 2 2026-04-30 2026-09-30
www.nu.co 10 2026-05-17 2026-09-08

Programmatic access: API GET /v1/hosts/nu.co (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/nu.co.