Frequently asked questions

CGNAT stands for Carrier-Grade Network Address Translation. It lets an ISP place many customers behind shared public IPv4 addresses instead of assigning a unique public IPv4 address to each customer.

No. This is a best-effort browser check. It can highlight strong signs of CGNAT, but it cannot confirm every network layout or ISP setup from the browser alone.

If your router shows a private or shared CGNAT address on its WAN or internet page, that usually means another layer of NAT exists upstream. In many cases that prevents direct inbound connections and port forwarding from working as expected.

Matching public IPv4 addresses are a strong sign that you are not behind standard IPv4 CGNAT, but they do not rule out every unusual network setup, firewall policy, or ISP restriction.

Ask whether your current plan uses CGNAT, whether a public IPv4 address is available, whether a static IP option exists, and whether any plan or regional differences apply to your account.

Sometimes. IPv6 can make direct inbound connectivity possible without the same IPv4 CGNAT limitation, but the exact behavior depends on your router, firewall rules, and ISP setup.