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.

19 hosts · 314 ms

HostCertsFirst seenLast seenDNS
ernesta.com 23 2026-04-15 2026-10-06 ok
*.ernesta.com 17 2026-04-20 2026-10-06 —
hd.ernesta.com 2 2025-08-27 2026-07-28 ok
prod.ernesta.com 4 2026-04-14 2026-08-11 ok
sizing.ernesta.com 4 2026-04-19 2026-09-04 ok
auth.ernesta.com 10 2026-05-01 2026-08-28 ok
api.ernesta.com 5 2026-05-16 2026-09-14 ok
internal.helpdesk.ernesta.com 2 2025-08-27 2026-07-28 ok
retool.ernesta.com 11 2026-05-25 2026-09-03 ok
cloud.m.ernesta.com 1 2026-02-13 2026-02-13 ok
image.m.ernesta.com 4 2026-01-29 2026-08-10 ok
click.m.ernesta.com 2 2026-02-13 2026-02-13 ok
view.m.ernesta.com 1 2026-02-13 2026-02-13 ok
login.ernesta.com 12 2026-04-30 2026-10-02 ok
imgs.ernesta.com 6 2026-05-15 2026-09-13 ok
rugs.ernesta.com 5 2026-04-26 2026-09-11 ok
checkout.ernesta.com 4 2026-04-14 2026-08-12 ok
www.ernesta.com 4 2026-04-13 2026-08-10 ok
app-shopify.ernesta.com 5 2026-05-15 2026-09-14 ok

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