Find every subdomain
of a domain.

Every hostname under a domain that ever appeared in a public TLS certificate — with certificate counts and first/last seen dates.

14 hosts · 314 ms

HostCertsFirst seenLast seen
syniumsoftware.com 2 2026-03-17 2026-08-17
*.syniumsoftware.com 3 2026-03-05 2026-08-17
download.syniumsoftware.com 5 2026-04-30 2026-08-18
finance.syniumsoftware.com 5 2026-04-30 2026-08-18
ifinance.syniumsoftware.com 2 2026-03-06 2026-06-30
api.syniumsoftware.com 2 2026-03-06 2026-06-30
mail.syniumsoftware.com 5 2026-05-16 2026-09-13
webmail.syniumsoftware.com 5 2026-05-16 2026-09-13
ifwp.syniumsoftware.com 5 2026-04-30 2026-08-18
ads.syniumsoftware.com 4 2026-04-18 2026-08-16
versions.syniumsoftware.com 5 2026-04-30 2026-08-18
stats.syniumsoftware.com 5 2026-04-30 2026-08-18
logoist.syniumsoftware.com 1 2025-09-18 2025-09-18
notify.syniumsoftware.com 5 2026-05-04 2026-09-01

Programmatic access: API GET /v1/hosts/syniumsoftware.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/syniumsoftware.com.