Blog · Basics
Shared IP address: real vs shared IP
Short answer: A shared IP is one public address used by many devices or many customers at once. Every home router shares one IP across your devices, and many mobile and some home ISPs share one IP across hundreds of customers (CGNAT). A real or dedicated IP belongs to your connection alone.
How to check if you have a real IP or a shared IP
- Note the public IP in the bar at the top of this page.
- Open your router's admin page and find the WAN or Internet IP.
- If both match, you have a real public IP (it may still be dynamic).
- If the router shows
100.64.x.x–100.127.x.x,10.x.x.xor anything different, your ISP puts you behind CGNAT and the IP is shared.
On mobile data, a shared IP is normal. See mobile data vs Wi-Fi public IP.
Why it matters
- Hosting and games: behind a shared IP you cannot open ports, so others cannot join a server you host.
- Blocks and CAPTCHAs: if someone else on the same IP misbehaves, you can hit CAPTCHAs or blocks. See IP reputation and blacklists.
- Privacy: a shared IP blends you with other users, which slightly helps privacy.
"Another computer is using your IP address"
This message, or "IP address conflict", is about your local network. Two devices got the same 192.168 address, usually because one has a manually set (static) IP. Fix it by restarting the router, or by setting both devices to obtain an address automatically (DHCP). It does not mean a stranger has taken your public IP.
Who assigns public IP addresses?
IANA hands large blocks to five regional registries (ARIN, RIPE NCC, APNIC, LACNIC, AFRINIC). The registries allocate them to ISPs and hosting companies, and your ISP assigns one to your connection, usually automatically and often temporarily. That is why your public IP can change. IPv4 addresses ran short, which is why sharing is so common. See IPv4 exhaustion and IPv6.
Can I get a real IP?
Most ISPs sell a dedicated or static IP as an add-on. Ask for a "public" or "white" IP. IPv6, where available, gives each device its own global address, so check why IPv6 is not showing too.
FAQ
What is a shared IP address?
One public IP used by many devices or customers at the same time, through your router or your ISP's carrier-grade NAT.
How do I check if my IP is real or shared?
Compare the public IP shown on this site with the WAN IP on your router. If they differ, or the router shows 100.64.x.x, the IP is shared.
What does "another computer is using your IP address" mean?
Two devices on your local network have the same private address. Restart the router or switch both to automatic (DHCP) addressing.
Who assigns public IP addresses?
IANA gives blocks to regional registries, they allocate them to ISPs, and your ISP assigns one to your connection.