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.

7 hosts · 214 ms

HostCertsFirst seenLast seenDNS
tons.bike 21 2026-04-26 2026-09-30 ok
*.tons.bike 5 2026-04-26 2026-08-24 —
dashboard.tons.bike 4 2026-04-15 2026-08-14 ok
www.dashboard.tons.bike 4 2026-04-15 2026-08-14 ok
m.tons.bike 6 2026-06-06 2026-08-04 ok
account.tons.bike 1 2026-09-15 2026-09-15 ok
www.tons.bike 17 2026-05-19 2026-09-29 ok

Programmatic access, with DNS A records: API GET /v1/hosts/tons.bike (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/tons.bike.