What Are CGNAT / Shared IP, and How to Detect Them
CGNAT (carrier-grade NAT) is a technique ISPs use to let many users share one public IP, easing the shortage of IPv4 addresses.
Behind CGNAT you have no dedicated public IP, cannot do port forwarding or direct inbound connections, and share the same exit IP with others, which means their behavior can drag your reputation down.
How to detect it
If your router's WAN IP is a carrier private range like 100.64.0.0/10 and differs from the public exit IP shown on this site, you are behind CGNAT.
What the impact is
No direct inbound connections or port forwarding; the fraud and blocklist risk of the shared exit IP is spread across many users.
FAQ
- Can CGNAT be fixed?
- You can ask your ISP for a public IP (free or paid depending on the region), or use IPv6 or NAT-traversal solutions.
- Does a shared IP affect TikTok / sign-ups?
- It can. Once a shared exit IP is abused by someone else, its risk score and blocklist status drag you down too.
Want to check a specific IP? Enter it on thehome pageto see its full details: location, IP type, risk score, blocklist status and more.
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