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.

8 hosts · 267 ms

HostCertsFirst seenLast seenDNS
nebulasoftware.com 14 2026-04-12 2026-10-05 ok
clk.nebulasoftware.com 5 2026-05-10 2026-09-07 ok
cdn.nebulasoftware.com 11 2026-04-22 2026-10-04 ok
displayswitcherserver.nebulasoftware.com 1 2026-08-05 2026-08-05 ok
docs.nebulasoftware.com 10 2026-04-20 2026-08-17 ok
updates.nebulasoftware.com 5 2026-04-11 2026-09-23 ok
videos.nebulasoftware.com 4 2026-04-26 2026-07-20 ok
www.nebulasoftware.com 16 2026-04-11 2026-10-05 ok

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