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.

60 hosts · 354 ms

HostCertsFirst seenLast seenDNS
tstllc.net 5 2025-07-18 2026-09-21 ok
*.tstllc.net 8 2025-07-18 2026-09-21 —
*.infra.tstllc.net 5 2026-05-22 2026-09-21 —
*.infra1.infra.tstllc.net 4 2026-06-06 2026-10-05 —
*.nonprod1.infra.tstllc.net 4 2026-06-07 2026-10-06 —
*.prod3.infra.tstllc.net 4 2026-06-07 2026-10-05 —
*.prod4.infra.tstllc.net 4 2026-06-04 2026-10-03 —
*.qa.infra.tstllc.net 4 2026-04-30 2026-06-30 —
*.blue.infra.tstllc.net 5 2026-04-29 2026-08-29 —
*.ref.infra.tstllc.net 5 2026-04-29 2026-08-27 —
*.staging.infra.tstllc.net 4 2026-04-28 2026-06-27 —
*.cstaging.infra.tstllc.net 4 2026-05-23 2026-07-23 —
*.training.infra.tstllc.net 5 2026-05-16 2026-09-14 —
*.eck.infra.tstllc.net 5 2026-05-03 2026-08-31 —
*.green.infra.tstllc.net 5 2026-04-29 2026-08-27 —
*.train.infra.tstllc.net 4 2026-04-29 2026-06-28 —
*.analytics.infra.tstllc.net 4 2026-05-12 2026-07-14 —
*.uat.infra.tstllc.net 4 2026-05-26 2026-07-26 —
*.client.infra.tstllc.net 4 2026-05-25 2026-07-24 —
*.test.infra.tstllc.net 5 2026-04-27 2026-08-26 —
*.locust.infra.tstllc.net 4 2026-04-30 2026-06-29 —
*.dev.infra.tstllc.net 5 2026-05-29 2026-09-27 —
*.cdev.infra.tstllc.net 4 2026-05-28 2026-07-28 —
*.preview.infra.tstllc.net 5 2026-05-15 2026-09-12 —
*.pfix.infra.tstllc.net 4 2026-05-24 2026-07-24 —
envoy.infra.tstllc.net 2 2026-06-04 2026-06-04 ok
active-directory.infra.tstllc.net 2 2025-08-29 2025-08-29 ok
okta.tstllc.net 9 2026-04-13 2026-09-20 ok
api.playground.tstllc.net 2 2026-02-21 2026-07-09 ok
platform.playground.tstllc.net 2 2026-02-21 2026-07-09 ok
*.kube.tstllc.net 5 2026-05-25 2026-09-24 —
*.qa.kube.tstllc.net 4 2026-04-28 2026-06-28 —
*.dataload.kube.tstllc.net 5 2026-05-25 2026-09-22 —
*.prod.kube.tstllc.net 5 2026-04-27 2026-08-26 —
*.blue.kube.tstllc.net 5 2026-05-26 2026-09-25 —
*.ref.kube.tstllc.net 5 2026-04-28 2026-08-27 —
*.staging.kube.tstllc.net 4 2026-04-28 2026-06-28 —
*.green.kube.tstllc.net 5 2026-05-29 2026-09-27 —
*.demo.kube.tstllc.net 5 2026-05-25 2026-09-22 —
*.micro.kube.tstllc.net 4 2026-05-26 2026-07-26 —
jenkins.kube.tstllc.net 5 2026-05-24 2026-09-23 ok
*.uat.kube.tstllc.net 4 2026-04-30 2026-06-30 —
*.client.kube.tstllc.net 4 2026-05-26 2026-07-26 —
*.test.kube.tstllc.net 5 2026-04-28 2026-08-28 —
*.dev.kube.tstllc.net 5 2026-05-23 2026-09-20 —
*.replay.kube.tstllc.net 4 2026-04-28 2026-06-28 —
*.active.tstllc.net 5 2026-05-25 2026-09-23 —
*.inactive.tstllc.net 5 2026-05-23 2026-09-20 —
staging.tstllc.net 1 2026-07-28 2026-07-28 ok
*.staging.tstllc.net 1 2026-07-28 2026-07-28 —
releases.tstllc.net 5 2026-05-17 2026-09-15 ok
apis.tstllc.net 2 2025-08-22 2026-07-23 ok
webhooks.tstllc.net 1 2025-08-20 2025-08-20 nxdomain
www.webhooks.tstllc.net 1 2025-08-20 2025-08-20 nxdomain
developers.tstllc.net 5 2026-05-24 2026-09-21 ok
incidents.tstllc.net 5 2026-05-09 2026-09-05 ok
deployments.tstllc.net 4 2026-06-01 2026-09-20 ok
apis-uat.tstllc.net 1 2025-12-24 2025-12-24 ok
connect.tstllc.net 2 2026-09-30 2026-09-30 ok
apis-dev.tstllc.net 2 2025-08-22 2026-07-23 ok

Programmatic access, with DNS A records: API GET /v1/hosts/tstllc.net (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/tstllc.net.