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.

23 hosts · 283 ms

HostCertsFirst seenLast seenDNS
htp.org 43 2026-04-15 2026-08-29 ok
*.htp.org 21 2026-04-25 2026-08-29 —
static.htp.org 1 2025-12-04 2025-12-04 ok
service.htp.org 5 2026-05-11 2026-09-09 ok
share.htp.org 5 2026-05-05 2026-09-20 ok
store.htp.org 12 2026-04-09 2026-10-04 ok
email.mg.htp.org 5 2026-05-17 2026-09-14 ok
giving.htp.org 12 2026-04-12 2026-08-08 ok
api.htp.org 8 2026-04-15 2026-08-12 nxdomain
giving.hk.htp.org 10 2026-04-17 2026-08-13 ok
link.htp.org 5 2026-04-25 2026-08-23 ok
giving.uk.htp.org 8 2026-04-17 2026-08-13 ok
mail.htp.org 5 2026-05-05 2026-09-03 ok
petition.htp.org 10 2026-04-09 2026-10-03 ok
go.htp.org 5 2026-05-06 2026-09-04 ok
partner.htp.org 2 2026-05-13 2026-09-05 ok
stories.htp.org 6 2026-05-21 2026-09-16 ok
signals.htp.org 12 2026-05-26 2026-09-22 ok
connect.htp.org 8 2026-04-28 2026-08-24 ok
meet.htp.org 10 2026-05-10 2026-09-05 ok
report.htp.org 8 2026-04-13 2026-08-09 ok
giving.au.htp.org 8 2026-04-18 2026-08-15 ok
www.htp.org 2 2026-08-25 2026-08-25 ok

Programmatic access, with DNS A records: API GET /v1/hosts/htp.org (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/htp.org.