Check Real IP or Shared IP: How to Tell What Websites Can See

"Real IP" is a slippery phrase. In most everyday cases, it means the public IP websites can see when your browser connects to them.

That visible address may be direct from your ISP. It may also be shared through a router, mobile carrier, CGNAT gateway, VPN, proxy, office firewall, hotel Wi-Fi, or hosting network.

Start with IP Address Lookup. Then read the provider, ASN, and security context before deciding what kind of IP you are looking at.

Fast check

Use this sequence:

1. Disconnect VPN or proxy if you want to test your baseline ISP connection.
2. Open FindMyIP.uk.
3. Record the public IP, ASN, provider, and approximate location.
4. Turn the VPN or proxy back on, or switch from Wi-Fi to mobile data.
5. Run the lookup again and compare the result.

If the visible IP changes, websites are seeing the new network path. If the address stays the same, that path may not be affecting browser traffic.

How one public IP can be shared

Many users can appear behind the same public IP. Common reasons include:

• home router NAT
• office or school gateways
• hotel and cafe Wi-Fi
• mobile carrier CGNAT
• VPN exit servers
• public proxies
• cloud load balancers

That is why an IP address is not the same as a person or one device.

What CGNAT means

CGNAT stands for carrier-grade NAT. It lets an ISP or mobile carrier place many customers behind shared public IPv4 addresses.

You may notice CGNAT when:

• port forwarding does not work from outside
• your router's WAN address differs from the public IP shown by a lookup tool
• game hosting or self-hosting fails from the open internet
• several users appear to share one carrier-owned address

CGNAT is common on mobile networks and some residential providers.

VPN and proxy shared IPs

VPN and proxy services often put many users behind the same exit IP. That is expected.

The lookup result may show:

• a hosting network
• a data center ASN
• a country or city chosen by the exit server
• VPN, proxy, Tor, or datacenter signals

If you are testing privacy routing, read how to check if your VPN is working.

How to tell whether the IP is probably shared

No single field proves it, but the clues stack up:

• The ASN belongs to a mobile carrier, VPN, proxy, hosting provider, or office network.
• The location is a hub city rather than your actual city.
• Your router WAN address is private or carrier-grade while the lookup shows a different public address.
• Multiple devices on the same network show the same public IP.
• The address changes when you switch networks or turn VPN routing on.

For local address confusion, read private IP address lookup.

FAQ

Is a shared IP bad?

Not by itself. Shared IPs are normal on home networks, mobile networks, workplaces, VPNs, and proxies. They only become a problem when you need inbound access, clean attribution, or reputation separation.

Can a website see my private IP?

Usually no. Websites normally see the public IP used by your router, carrier, VPN, proxy, or gateway. Your private LAN address stays inside your local network.

Does a VPN hide my real IP?

It can hide your baseline ISP public IP from the website you visit by replacing it with a VPN exit IP. It does not make you invisible, and the VPN exit may still be a shared public address.

Can I tell exactly who else shares my IP?

No. A public lookup can show network context, but it cannot list the people or devices sharing that address.