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.

15 hosts · 295 ms

HostCertsFirst seenLast seenDNS
hexfit.com 13 2026-05-17 2026-09-30 ok
*.hexfit.com 9 2026-05-17 2026-09-01 —
strava.hexfit.com 1 2026-09-13 2026-09-13 ok
wiki.hexfit.com 4 2026-04-14 2026-08-12 ok
feedback.hexfit.com 12 2026-05-08 2026-09-04 ok
go.hexfit.com 16 2026-05-09 2026-09-04 ok
fkq.hexfit.com 8 2026-04-16 2026-08-12 ok
custom-app-designer.hexfit.com 5 2026-05-23 2026-09-20 ok
docs.hexfit.com 5 2026-05-22 2026-09-19 ok
funds.hexfit.com 11 2026-05-26 2026-09-22 ok
affiliates.hexfit.com 5 2026-05-13 2026-09-15 ok
status.hexfit.com 2 2026-10-01 2026-10-01 ok
mkt.hexfit.com 16 2026-05-12 2026-09-07 ok
trust.hexfit.com 3 2026-10-01 2026-10-01 ok
www.hexfit.com 6 2026-09-30 2026-09-30 ok

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