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.

13 hosts · 315 ms

HostCertsFirst seenLast seenDNS
helpling.de 29 2025-11-03 2026-10-04 ok
*.helpling.de 25 2025-11-03 2026-10-04 —
static.helpling.de 1 2026-06-23 2026-06-23 ok
sendgrid.helpling.de 1 2026-05-29 2026-05-29 ok
stagingsendgrid.helpling.de 2 2026-05-28 2026-05-28 ok
clicks-staging.helpling.de 1 2026-05-29 2026-05-29 ok
help.helpling.de 6 2026-06-25 2026-08-23 ok
app.helpling.de 4 2025-09-18 2026-10-05 ok
clicks.helpling.de 1 2026-05-29 2026-05-29 ok
assets.helpling.de 1 2026-05-27 2026-05-27 ok
sst.helpling.de 3 2026-05-17 2026-08-31 ok
gettoknow.helpling.de 5 2026-05-23 2026-09-20 ok
www.helpling.de 4 2026-04-12 2026-08-12 ok

Programmatic access, with DNS A records: API GET /v1/hosts/helpling.de (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/helpling.de.