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.

14 hosts · 305 ms

HostCertsFirst seenLast seenDNS
firstleaf.com 47 2025-06-26 2026-09-29 ok
*.firstleaf.com 27 2025-06-26 2026-09-29 —
page.firstleaf.com 2 2026-05-11 2026-05-11 ok
share.firstleaf.com 3 2026-04-16 2026-06-14 ok
tracking.firstleaf.com 12 2026-05-09 2026-09-04 ok
find-msg.firstleaf.com 8 2026-05-11 2026-09-06 ok
fbapi.firstleaf.com 2 2026-03-23 2026-04-07 ok
*.fbapi.firstleaf.com 1 2026-04-07 2026-04-07 —
scim.firstleaf.com 4 2026-04-24 2026-05-14 ok
help.firstleaf.com 5 2026-04-26 2026-08-24 ok
links.firstleaf.com 10 2026-05-20 2026-09-15 ok
account.firstleaf.com 5 2026-05-12 2026-09-09 ok
www.firstleaf.com 5 2026-05-21 2026-09-17 ok
shopify.firstleaf.com 6 2026-04-11 2026-04-24 nxdomain

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