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.

27 hosts · 521 ms

HostCertsFirst seenLast seenDNS
thebigwhale.io 16 2026-05-17 2026-09-22 ok
*.thebigwhale.io 6 2026-05-23 2026-09-22 —
api.valid.thebigwhale.io 4 2026-06-04 2026-10-03 ok
mcp.valid.thebigwhale.io 4 2026-06-04 2026-10-03 ok
dashboard.thebigwhale.io 4 2026-04-17 2026-08-15 ok
edito-dashboard.thebigwhale.io 5 2026-05-11 2026-09-08 ok
marketing.thebigwhale.io 5 2026-05-11 2026-09-07 ok
outreach.thebigwhale.io 5 2026-05-13 2026-09-10 ok
agent-api.thebigwhale.io 5 2026-04-22 2026-08-20 ok
cdn.thebigwhale.io 9 2026-05-28 2026-09-23 ok
translation.thebigwhale.io 5 2026-05-22 2026-09-19 ok
edito.thebigwhale.io 2 2026-05-07 2026-05-07 ok
mcp.thebigwhale.io 5 2026-04-22 2026-08-20 ok
app.thebigwhale.io 8 2026-04-14 2026-08-10 ok
sonar.thebigwhale.io 4 2026-04-17 2026-08-15 ok
img.newsletter.thebigwhale.io 12 2026-05-08 2026-09-03 ok
r.newsletter.thebigwhale.io 3 2026-05-17 2026-08-05 ok
breakfasts.thebigwhale.io 5 2026-05-14 2026-09-10 ok
chat.thebigwhale.io 5 2026-05-26 2026-09-23 ok
theagent-chat.thebigwhale.io 7 2026-04-23 2026-09-21 ok
workshop-summit.thebigwhale.io 3 2026-07-13 2026-09-11 ok
cockpit.thebigwhale.io 4 2026-04-17 2026-08-15 ok
agent.thebigwhale.io 5 2026-05-19 2026-09-15 ok
theagent.thebigwhale.io 7 2026-04-27 2026-09-22 ok
www.thebigwhale.io 12 2026-05-17 2026-09-13 ok
deploy.thebigwhale.io 5 2026-05-13 2026-09-10 ok
privy.thebigwhale.io 5 2026-05-27 2026-09-28 ok

Programmatic access, with DNS A records: API GET /v1/hosts/thebigwhale.io (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/thebigwhale.io.