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.

21 hosts · 212 ms

HostCertsFirst seenLast seen
ur.io 56 2026-04-15 2026-09-18
*.ur.io 16 2026-05-23 2026-09-18
main-grafana.ur.io 9 2026-07-19 2026-09-03
main-web.ur.io 17 2026-04-15 2026-09-03
main-lb.ur.io 17 2026-04-15 2026-09-03
main-api.ur.io 17 2026-04-15 2026-09-03
feedback.ur.io 12 2026-06-03 2026-09-29
main-mcp.ur.io 17 2026-04-15 2026-09-03
shop.ur.io 16 2026-05-07 2026-09-17
account.shop.ur.io 13 2026-05-15 2026-09-24
main-app.ur.io 17 2026-04-15 2026-09-03
newsletter.ur.io 11 2026-06-08 2026-10-04
docs.ur.io 6 2026-05-26 2026-07-24
img.updates.ur.io 6 2026-05-02 2026-08-28
r.updates.ur.io 4 2026-05-07 2026-07-26
status.ur.io 4 2026-06-06 2026-10-03
main-connect.ur.io 17 2026-04-15 2026-09-03
preview.ur.io 17 2026-04-15 2026-09-03
www.ur.io 23 2026-04-15 2026-09-03
pay.ur.io 13 2026-06-09 2026-10-06
main-proxy.ur.io 17 2026-04-15 2026-09-03

Programmatic access: API GET /v1/hosts/ur.io (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/ur.io.