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 · 274 ms

HostCertsFirst seenLast seenDNS
saily.com 25 2026-05-16 2026-10-05 ok
*.saily.com 16 2026-05-21 2026-09-16 —
obs.infra.saily.com 1 2025-12-08 2025-12-08 nodata
*.obs.infra.saily.com 1 2025-12-08 2025-12-08 —
geolocation-feed.saily.com 7 2026-05-16 2026-09-11 ok
cisionone-email.saily.com 5 2026-04-28 2026-08-26 ok
cms.saily.com 2 2026-10-05 2026-10-05 ok
*.cms.saily.com 2 2026-10-05 2026-10-05 —
support.saily.com 4 2026-04-19 2026-08-17 ok
survey.saily.com 9 2026-05-28 2026-09-23 ok

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