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.

4 hosts · 258 ms

HostCertsFirst seenLast seen
indebted.us 2 2026-05-06 2026-10-06
*.indebted.us 2 2026-05-06 2026-10-06
payment.indebted.us 5 2026-05-22 2026-09-21
pay.indebted.us 5 2026-04-22 2026-08-20

Programmatic access: API GET /v1/hosts/indebted.us (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/indebted.us.