The short answer
A public IP address is unique on the whole internet and is what websites see. A private IP address is only valid inside a local network, such as your home Wi-Fi, and is never seen directly by websites. Your router has one public address and hands out private addresses to every device behind it.
See your public address now on the My IP page, and how to find the private one in how to find your IP address.
Public vs private at a glance
| Public IP | Private IP | |
|---|---|---|
| Unique | Worldwide | Only within your network |
| Assigned by | Your internet provider | Your router (DHCP) |
| Visible to websites | Yes | No |
| Example | 203.0.113.42 | 192.168.1.23 |
| Can be looked up | Yes, location and provider | No, it means nothing outside your network |
Private IP address ranges
These ranges are reserved for private networks and are never routed on the internet:
| Range | Size | Common use |
|---|---|---|
10.0.0.0 to 10.255.255.255 | 16.7 million addresses | Large companies, some routers, VPNs |
172.16.0.0 to 172.31.255.255 | 1 million addresses | Offices, Docker and cloud networks |
192.168.0.0 to 192.168.255.255 | 65,536 addresses | Most home routers |
100.64.0.0 to 100.127.255.255 | 4 million addresses | Carrier-grade NAT between provider and customer |
For IPv6, addresses starting with fd or fc are private (unique local), and those starting with fe80 only work on the same link.
If you look up any of these in the IP lookup, it tells you the address is private rather than showing a location.
How NAT connects them
When your laptop at 192.168.1.23 opens a website, your router replaces the private source address with its public one and remembers the connection. When the answer comes back, it forwards it to your laptop. This is NAT (network address translation). It's what lets dozens of devices share one public IPv4 address, and it also blocks unsolicited connections from the internet, which is why hosting a server at home needs port forwarding.
Carrier-grade NAT: when your "public" IP isn't yours
Because IPv4 addresses ran out, many mobile and some home providers add a second layer of NAT. Your router then gets an address from 100.64.0.0/10 (or another private range) instead of a public one, and many customers share one public IP.
You can spot this by comparing the WAN or internet address on your router's status page with the address on the My IP page. If they differ, you're behind carrier-grade NAT. Port forwarding won't work, and you may share bans and CAPTCHAs with your neighbors. Ask your provider for a public IP, or use IPv6, which doesn't need NAT. See IPv4 vs IPv6.
FAQ
Can two devices have the same private IP?
Yes, as long as they're on different networks. Millions of homes use 192.168.1.1 for their router. Two devices on the same network can't share one; that causes an IP conflict.
Is my private IP address a security risk?
Hardly. It only works inside your network. Browsers can reveal it through WebRTC, which helps websites fingerprint you, so it's worth limiting; see how to disable WebRTC.
Why does my router show a different public IP than websites?
Your provider is using carrier-grade NAT, or there's another router in front of yours. Websites show the address your traffic finally leaves from.
Does a VPN change my private IP?
It adds one. The VPN gives your device an address inside its own private network, and your public IP becomes the VPN server's. Your home network address stays the same.