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.

9 hosts · 257 ms

HostCertsFirst seenLast seenDNS
cityofmerced.gov 7 2026-04-28 2026-09-08 ok
engage.cityofmerced.gov 5 2026-05-25 2026-09-22 ok
www.engage.cityofmerced.gov 5 2026-05-25 2026-09-22 ok
vpn.cityofmerced.gov 2 2025-12-09 2025-12-09 ok
automator.cityofmerced.gov 3 2025-07-28 2026-08-20 nxdomain
apps.cityofmerced.gov 1 2026-05-12 2026-05-12 ok
comnet.cityofmerced.gov 1 2026-09-10 2026-09-10 nxdomain
publiccomment.cityofmerced.gov 3 2026-05-19 2026-09-26 ok
www.cityofmerced.gov 15 2026-04-15 2026-09-10 ok

Programmatic access, with DNS A records: API GET /v1/hosts/cityofmerced.gov (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/cityofmerced.gov.