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 · 220 ms

HostCertsFirst seenLast seenDNS
marinelayer.com 17 2026-05-16 2026-09-24 ok
trk.send.marinelayer.com 6 2026-04-15 2026-08-11 ok
cdn.marinelayer.com 4 2026-06-07 2026-10-07 ok
analytics.marinelayer.com 5 2026-04-16 2026-09-25 ok
www.analytics.marinelayer.com 4 2026-04-16 2026-09-22 ok
sms.marinelayer.com 10 2026-05-09 2026-09-05 ok
returns.marinelayer.com 10 2026-05-16 2026-09-11 ok
account.marinelayer.com 7 2026-05-03 2026-09-01 ok
www.marinelayer.com 6 2026-05-14 2026-09-09 ok
survey.marinelayer.com 5 2026-05-15 2026-09-12 ok

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