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.

9 hosts · 356 ms

HostCertsFirst seenLast seenDNS
quadlockcase.com 7 2026-04-22 2026-08-19 ok
custom-case.quadlockcase.com 16 2026-05-24 2026-10-03 ok
affiliates.quadlockcase.com 5 2026-05-11 2026-09-08 ok
webhooks.quadlockcase.com 5 2026-05-13 2026-09-11 ok
sms.quadlockcase.com 10 2026-05-09 2026-09-04 ok
content.quadlockcase.com 5 2026-05-15 2026-09-13 ok
account.quadlockcase.com 13 2026-05-26 2026-10-04 ok
support.quadlockcase.com 5 2026-05-03 2026-08-31 ok
www.quadlockcase.com 15 2026-05-16 2026-09-23 ok

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