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.

10 hosts · 297 ms

HostCertsFirst seenLast seenDNS
zamnesia.com 17 2026-05-14 2026-10-03 ok
*.zamnesia.com 17 2026-05-14 2026-10-03 —
affiliate.zamnesia.com 1 2026-01-06 2026-01-06 ok
t.marketing.zamnesia.com 5 2026-06-02 2026-08-01 ok
trk.zamnesia.com 4 2026-05-09 2026-07-24 ok
metrics.zamnesia.com 2 2026-05-03 2026-05-03 nxdomain
load.metrics.zamnesia.com 2 2026-05-18 2026-05-18 nxdomain
mta-sts.zamnesia.com 3 2026-06-26 2026-09-17 ok
support.zamnesia.com 1 2026-08-28 2026-08-28 ok
monday.zamnesia.com 5 2026-05-05 2026-09-03 ok

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