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.

12 hosts · 293 ms

HostCertsFirst seenLast seenDNS
thuma.co 13 2026-05-17 2026-09-25 ok
cdi2.thuma.co 1 2026-01-26 2026-01-26 nodata
col.cdi2.thuma.co 2 2026-01-26 2026-06-12 ok
ts.cdi2.thuma.co 2 2026-01-26 2026-06-12 ok
rt8cfew9.thuma.co 65 2026-04-29 2026-08-23 ok
ssc.thuma.co 4 2026-09-14 2026-09-14 ok
tag.thuma.co 3 2026-05-25 2026-09-10 ok
trail.thuma.co 5 2026-05-17 2026-08-23 ok
*.vip.thuma.co 4 2025-09-11 2026-08-12 —
checkout.thuma.co 13 2026-04-11 2026-09-24 ok
new.thuma.co 2 2026-05-09 2026-05-09 ok
www.thuma.co 7 2026-04-19 2026-08-28 ok

Programmatic access, with DNS A records: API GET /v1/hosts/thuma.co (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/thuma.co.