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.

52 hosts · 411 ms

HostCertsFirst seenLast seenDNS
serko.ai 4 2026-04-15 2026-08-17 ok
langfuse.serko.ai 6 2026-04-15 2026-09-27 ok
langfuse.staging.serko.ai 5 2026-05-16 2026-09-19 ok
auth.staging.serko.ai 6 2026-06-29 2026-09-29 ok
admin.staging.serko.ai 3 2026-07-23 2026-09-19 ok
app.staging.serko.ai 5 2026-05-16 2026-09-19 ok
docs.staging.serko.ai 5 2026-05-16 2026-09-19 ok
tools.staging.serko.ai 5 2026-05-16 2026-09-19 ok
api.confident.staging.serko.ai 10 2026-08-01 2026-09-25 ok
otel.confident.staging.serko.ai 10 2026-08-01 2026-09-25 ok
mcp.confident.staging.serko.ai 6 2026-08-22 2026-09-01 ok
app.confident.staging.serko.ai 10 2026-08-01 2026-09-25 ok
evals.confident.staging.serko.ai 10 2026-08-01 2026-09-25 ok
waitlist.staging.serko.ai 5 2026-05-16 2026-09-19 ok
auth.serko.ai 6 2026-06-29 2026-09-29 ok
admin.serko.ai 6 2026-04-15 2026-09-27 ok
app.serko.ai 6 2026-04-15 2026-09-27 ok
docs.serko.ai 6 2026-04-15 2026-09-27 ok
clicks.serko.ai 3 2026-05-22 2026-09-04 ok
tools.serko.ai 6 2026-04-15 2026-09-27 ok
mta-sts.serko.ai 1 2026-09-07 2026-09-07 ok
admin.uat.serko.ai 1 2026-04-16 2026-04-16 nxdomain
app.uat.serko.ai 1 2026-04-16 2026-04-16 nxdomain
api.confident.serko.ai 1 2026-08-14 2026-08-14 ok
otel.confident.serko.ai 1 2026-08-14 2026-08-14 ok
mcp.confident.serko.ai 1 2026-08-22 2026-08-22 ok
app.confident.serko.ai 1 2026-08-14 2026-08-14 ok
evals.confident.serko.ai 1 2026-08-14 2026-08-14 ok
support.serko.ai 5 2026-06-02 2026-08-18 ok
waitlist.serko.ai 3 2026-04-15 2026-08-01 ok
hello-world.dev.serko.ai 4 2026-06-17 2026-08-15 ok
langfuse.dev.serko.ai 5 2026-05-16 2026-09-14 ok
auth.dev.serko.ai 6 2026-06-28 2026-09-29 ok
lead-scorer-api.dev.serko.ai 4 2026-06-22 2026-08-14 ok
admin.dev.serko.ai 3 2026-07-23 2026-09-14 ok
hello.dev.serko.ai 2 2026-06-23 2026-06-23 nxdomain
app.dev.serko.ai 5 2026-05-16 2026-09-14 ok
lead-scorer.dev.serko.ai 4 2026-06-22 2026-08-19 ok
docs.dev.serko.ai 5 2026-05-16 2026-09-14 ok
tools.dev.serko.ai 5 2026-05-16 2026-09-14 ok
api.confident.dev.serko.ai 9 2026-08-08 2026-10-01 ok
otel.confident.dev.serko.ai 9 2026-08-08 2026-10-01 ok
mcp.confident.dev.serko.ai 7 2026-08-22 2026-09-01 ok
app.confident.dev.serko.ai 9 2026-08-08 2026-10-01 ok
evals.confident.dev.serko.ai 9 2026-08-08 2026-10-01 ok
waitlist.dev.serko.ai 5 2026-05-16 2026-09-14 ok
shared-gateway.dev.serko.ai 1 2026-08-21 2026-08-21 ok
www.serko.ai 7 2025-12-23 2026-09-27 ok
admin.canary.serko.ai 7 2026-04-13 2026-09-25 ok
app.canary.serko.ai 7 2026-04-13 2026-09-25 ok
docs.canary.serko.ai 1 2026-08-21 2026-08-21 ok
www.canary.serko.ai 1 2026-08-21 2026-08-21 ok

Programmatic access, with DNS A records: API GET /v1/hosts/serko.ai (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/serko.ai.