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.

44 hosts · 351 ms

HostCertsFirst seenLast seenDNS
101domain.com 9 2025-12-15 2026-08-16 ok
*.101domain.com 9 2025-12-15 2026-08-16 —
nagios-1a.us-west1.prod.101domain.com 5 2026-04-22 2026-08-21 ok
truemail-1a.or2.prod.101domain.com 2 2026-06-02 2026-06-02 ok
tor.prod.101domain.com 1 2025-10-07 2025-10-07 nodata
*.tor.prod.101domain.com 1 2025-10-07 2025-10-07 —
registry-admin.tor.prod.101domain.com 5 2026-05-02 2026-08-26 ok
registry.tor.prod.101domain.com 25 2026-05-31 2026-09-24 ok
forward-2a.kz.prod.101domain.com 5 2026-05-03 2026-09-01 ok
explore.101domain.com 8 2026-07-28 2026-09-25 ok
*.corporate.101domain.com 8 2026-04-19 2026-08-16 —
*.ote.101domain.com 18 2026-04-19 2026-08-16 —
api.ote.101domain.com 9 2026-05-27 2026-09-27 ok
reseller.ote.101domain.com 12 2026-06-02 2026-08-13 ok
my.ote.101domain.com 22 2026-05-28 2026-10-02 ok
*.staging.101domain.com 8 2026-04-19 2026-08-16 —
blog.101domain.com 18 2026-05-13 2026-10-03 ok
*.blog.101domain.com 14 2026-05-13 2026-09-08 —
www.blog.101domain.com 4 2026-06-05 2026-10-03 ok
tor.mgm.101domain.com 1 2026-05-18 2026-05-18 nodata
*.tor.mgm.101domain.com 1 2026-05-18 2026-05-18 —
n8n.101domain.com 2 2026-08-15 2026-08-15 ok
*.n8n.101domain.com 2 2026-08-15 2026-08-15 —
validation.101domain.com 2 2026-04-01 2026-09-28 ok
www.validation.101domain.com 2 2026-04-01 2026-09-28 nxdomain
help.101domain.com 1 2025-12-29 2025-12-29 ok
brandmonitor.101domain.com 2 2025-06-23 2026-06-22 ok
www.brandmonitor.101domain.com 2 2025-06-23 2026-06-22 nxdomain
admin-v4.fairwinds.101domain.com 10 2026-05-20 2026-09-15 ok
admin-v6.fairwinds.101domain.com 10 2026-05-20 2026-09-15 nodata
admin.fairwinds.101domain.com 10 2026-05-20 2026-09-15 ok
admin-prodtest.fairwinds.101domain.com 10 2026-05-30 2026-09-26 ok
mta-sts.101domain.com 2 2025-06-18 2026-05-19 ok
apt-client.101domain.com 2 2026-06-08 2026-06-09 nodata
www.apt-client.101domain.com 2 2026-06-08 2026-06-09 nxdomain
int.101domain.com 2 2025-07-30 2026-08-13 ok
*.int.101domain.com 2 2025-07-30 2026-08-13 —
vpn-7a.int.101domain.com 7 2026-04-20 2026-09-19 ok
api-prodtest.101domain.com 12 2026-06-05 2026-09-30 ok
dev.101domain.com 1 2025-11-12 2025-11-12 nodata
*.dev.101domain.com 9 2025-11-12 2026-08-16 —
*.nightly.101domain.com 8 2026-04-19 2026-08-16 —
registry.101domain.com 3 2025-09-16 2026-09-23 nodata
www.registry.101domain.com 3 2025-09-16 2026-09-23 nxdomain

Programmatic access, with DNS A records: API GET /v1/hosts/101domain.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/101domain.com.