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.

13 hosts · 261 ms

HostCertsFirst seenLast seen
3lc.ai 5 2026-04-28 2026-10-05
*.3lc.ai 2 2026-05-05 2026-10-05
pypi.3lc.ai 3 2025-08-11 2026-09-02
*.internal.3lc.ai 3 2026-03-18 2026-08-18
competitions.3lc.ai 2 2026-08-24 2026-08-24
mta-sts.3lc.ai 2 2025-09-11 2026-08-12
dev.3lc.ai 2 2026-02-23 2026-07-11
*.dev.3lc.ai 2 2026-02-23 2026-07-11
tools.dev.3lc.ai 2 2025-08-26 2026-07-27
competitions.dev.3lc.ai 4 2026-08-20 2026-08-24
identity.dev.3lc.ai 10 2026-06-08 2026-10-05
www.3lc.ai 3 2026-04-28 2026-08-30
identity.3lc.ai 9 2026-06-06 2026-10-04

Programmatic access: API GET /v1/hosts/3lc.ai (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/3lc.ai.