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.

21 hosts · 288 ms

HostCertsFirst seenLast seenDNS
activityinfo.org 4 2026-04-09 2026-09-16 ok
v4.activityinfo.org 5 2026-04-22 2026-10-01 ok
syria.activityinfo.org 6 2026-04-16 2026-09-28 ok
success.api.activityinfo.org 2 2026-03-25 2026-08-25 ok
help.activityinfo.org 3 2026-05-19 2026-09-02 ok
sop.activityinfo.org 2 2026-07-14 2026-09-07 ok
pui-ukr.activityinfo.org 3 2026-05-15 2026-08-28 ok
eltr.activityinfo.org 5 2026-05-21 2026-09-18 ok
caritas-spes.activityinfo.org 3 2026-05-15 2026-09-04 ok
courses.activityinfo.org 24 2026-04-22 2026-08-25 ok
alpha.customers.activityinfo.org 1 2026-08-17 2026-08-17 ok
carejo.customers.activityinfo.org 1 2026-08-17 2026-08-17 ok
success.activityinfo.org 2 2026-03-24 2026-08-24 ok
status.activityinfo.org 5 2026-04-25 2026-08-22 ok
trust.activityinfo.org 9 2026-06-01 2026-09-27 ok
about.activityinfo.org 3 2026-05-21 2026-09-07 ok
preview.activityinfo.org 4 2026-05-27 2026-09-14 ok
www.activityinfo.org 6 2026-04-09 2026-09-19 ok
ccy.activityinfo.org 3 2026-04-30 2026-08-17 ok
academy.activityinfo.org 3 2026-05-21 2026-09-06 ok
community.activityinfo.org 88 2026-05-29 2026-10-02 ok

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