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.

7 hosts · 326 ms

HostCertsFirst seenLast seenDNS
kingofchristmas.com 13 2026-05-17 2026-09-26 ok
bimi.kingofchristmas.com 1 2026-08-24 2026-08-24 ok
help.kingofchristmas.com 2 2026-04-02 2026-09-02 nodata
returns.kingofchristmas.com 3 2025-08-05 2026-08-20 nodata
account.kingofchristmas.com 14 2026-04-13 2026-09-26 ok
www.kingofchristmas.com 15 2026-05-16 2026-09-25 ok
koclegacy.kingofchristmas.com 2 2025-09-08 2026-08-20 nodata

Programmatic access, with DNS A records: API GET /v1/hosts/kingofchristmas.com (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/kingofchristmas.com.