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 · 244 ms

HostCertsFirst seenLast seenDNS
adafruit.com 17 2025-07-03 2026-09-28 ok
*.adafruit.com 17 2025-07-03 2026-09-28 —
statsd.adafruit.com 2 2026-08-24 2026-08-24 ok
makecode.adafruit.com 23 2026-02-02 2026-09-03 ok
i.adafruit.com 1 2026-07-06 2026-07-06 ok
learn.adafruit.com 1 2026-07-06 2026-07-06 ok
cdn-learn.adafruit.com 1 2026-07-06 2026-07-06 ok
accounts.adafruit.com 1 2026-07-06 2026-07-06 ok

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