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.

57 hosts · 402 ms

HostCertsFirst seenLast seenDNS
idahopower.com 4 2026-03-11 2026-08-11 ok
securemail2.idahopower.com 2 2025-08-07 2026-09-17 ok
vpn4.idahopower.com 7 2025-10-07 2026-10-02 ok
vpn5.idahopower.com 1 2025-12-10 2025-12-10 ok
vpn8.idahopower.com 1 2026-01-12 2026-01-12 ok
pra.idahopower.com 1 2025-12-31 2025-12-31 ok
apiedge.idahopower.com 2 2026-01-13 2026-06-10 ok
test.apiedge.idahopower.com 3 2026-05-13 2026-09-26 ok
remote.idahopower.com 2 2025-08-07 2026-08-03 ok
cmg.idahopower.com 1 2025-09-08 2025-09-08 nxdomain
ipcocmg.idahopower.com 2 2025-09-08 2026-08-18 ok
FileExch.idahopower.com 2 2026-06-11 2026-06-11 —
auth.idahopower.com 6 2025-09-09 2026-09-09 ok
staging.auth.idahopower.com 6 2025-09-09 2026-09-09 nxdomain
test.auth.idahopower.com 6 2025-09-09 2026-09-09 ok
dev.auth.idahopower.com 6 2025-09-09 2026-09-09 ok
api.idahopower.com 7 2026-03-03 2026-08-18 ok
ca.api.idahopower.com 3 2026-02-27 2026-08-14 ok
test.ca.api.idahopower.com 1 2026-01-06 2026-01-06 ok
dev.ca.api.idahopower.com 1 2026-01-06 2026-01-06 ok
test.api.idahopower.com 4 2026-01-30 2026-07-29 ok
dev.api.idahopower.com 2 2026-02-09 2026-07-29 ok
portal.idahopower.com 4 2025-10-01 2026-09-24 ok
gisportal.idahopower.com 1 2025-10-13 2025-10-13 ok
mail.idahopower.com 7 2025-08-20 2026-08-18 ok
securemail.idahopower.com 1 2026-05-08 2026-05-08 ok
idastream.idahopower.com 2 2026-05-04 2026-05-04 ok
spam.idahopower.com 4 2025-10-01 2026-09-24 nxdomain
vpn.idahopower.com 2 2025-09-29 2026-09-08 ok
Heyburn.idahopower.com 1 2025-12-10 2025-12-10 —
testipco.idahopower.com 2 2025-07-01 2026-06-25 ok
go.idahopower.com 1 2026-09-28 2026-09-28 ok
autodiscover.idahopower.com 7 2025-08-20 2026-08-18 ok
docs.idahopower.com 3 2026-05-12 2026-09-23 ok
tools.idahopower.com 6 2025-07-01 2026-06-25 ok
staging.tools.idahopower.com 6 2025-07-01 2026-06-25 nxdomain
test.tools.idahopower.com 6 2025-07-01 2026-06-25 ok
dev.tools.idahopower.com 8 2025-07-01 2026-07-29 ok
apps.idahopower.com 2 2025-08-07 2026-08-03 ok
fileexchtest.idahopower.com 4 2026-01-26 2026-07-14 ok
portaltest.idahopower.com 7 2025-09-17 2026-07-15 ok
gisportaltest.idahopower.com 1 2025-10-13 2025-10-13 ok
idastreamtest.idahopower.com 3 2026-05-04 2026-05-04 ok
heyburntest.idahopower.com 1 2025-12-10 2025-12-10 nxdomain
guest.idahopower.com 1 2025-11-26 2025-11-26 ok
aclararftst.idahopower.com 1 2026-09-18 2026-09-18 nxdomain
test.apigw.idahopower.com 3 2026-01-24 2026-07-09 ok
www.idahopower.com 3 2026-05-09 2026-09-20 ok
images.www.idahopower.com 3 2026-05-15 2026-09-28 ok
test.images.www.idahopower.com 3 2026-05-13 2026-09-25 ok
cms.www.idahopower.com 2 2026-05-17 2026-09-29 ok
test.cms.www.idahopower.com 3 2026-05-12 2026-09-24 ok
dev.cms.www.idahopower.com 1 2026-07-16 2026-07-16 ok
test.www.idahopower.com 3 2026-05-19 2026-10-01 ok
dev.www.idahopower.com 1 2026-07-16 2026-07-16 ok
my.idahopower.com 1 2025-10-28 2025-10-28 ok
snoopy.idahopower.com 1 2026-04-29 2026-04-29 nxdomain

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