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 · 290 ms

HostCertsFirst seenLast seenDNS
secnora.com 16 2026-05-03 2026-10-01 ok
*.secnora.com 6 2026-05-31 2026-10-01 —
sas-api.secnora.com 1 2026-09-14 2026-09-14 ok
app.secnora.com 3 2026-07-13 2026-09-11 ok
sas.secnora.com 1 2026-09-14 2026-09-14 ok
asvs.secnora.com 2 2026-05-02 2026-05-02 nxdomain
dev.secnora.com 3 2026-07-13 2026-09-10 ok
www.secnora.com 6 2026-05-05 2026-08-31 ok

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