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.

21 hosts · 346 ms

HostCertsFirst seenLast seenDNS
tommyjohn.com 23 2025-08-11 2026-09-26 ok
*.tommyjohn.com 8 2025-08-11 2026-08-25 —
claims2.tommyjohn.com 1 2025-06-26 2025-06-26 ok
161779.tommyjohn.com 1 2026-01-26 2026-01-26 ok
beta.tommyjohn.com 4 2026-04-20 2026-08-18 ok
staging.tommyjohn.com 13 2026-04-14 2026-09-27 ok
mi.tommyjohn.com 5 2026-05-05 2026-09-24 ok
click.tommyjohn.com 2 2026-04-11 2026-09-11 ok
trk.tommyjohn.com 1 2026-01-26 2026-01-26 ok
helpdesk.tommyjohn.com 12 2026-06-03 2026-09-29 ok
help.tommyjohn.com 4 2026-04-12 2026-08-10 ok
tjhq.tommyjohn.com 5 2026-05-18 2026-09-14 ok
ksdas.tommyjohn.com 7 2026-05-26 2026-09-21 ok
claims.tommyjohn.com 17 2025-06-26 2026-08-31 ok
functions.tommyjohn.com 4 2026-04-14 2026-08-12 ok
returns.tommyjohn.com 8 2026-05-15 2026-09-10 ok
tickets.tommyjohn.com 1 2025-11-20 2025-11-20 ok
*.tickets.tommyjohn.com 1 2025-11-20 2025-11-20 —
www.apollofast.tommyjohn.com 5 2026-05-16 2026-09-13 ok
www.tommyjohn.com 17 2026-05-17 2026-09-22 ok
privacy.tommyjohn.com 13 2026-05-23 2026-09-09 ok

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