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.

9 hosts · 329 ms

HostCertsFirst seenLast seenDNS
lumia.security 26 2026-04-18 2026-09-20 ok
*.lumia.security 15 2026-04-18 2026-08-14 —
bimi.lumia.security 2 2026-08-21 2026-08-21 ok
go.lumia.security 10 2026-05-07 2026-09-02 ok
labs.lumia.security 3 2026-06-24 2026-08-03 nxdomain
status.lumia.security 3 2026-08-01 2026-09-30 ok
assessment.lumia.security 2 2026-08-24 2026-08-24 ok
trust.lumia.security 4 2026-07-14 2026-09-12 ok
www.lumia.security 10 2026-05-25 2026-09-20 ok

Programmatic access, with DNS A records: API GET /v1/hosts/lumia.security (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/lumia.security.