A public IP address is the address visible on the internet. This is the address websites, online services, and remote servers usually see when your connection reaches them.
A private IP address is used inside a local network, such as your home, office, school, or Wi-Fi network. Your phone, computer, printer, smart TV, and router may all have private IP addresses on the same local network.
Your public IP address is assigned by your internet provider, mobile carrier, workplace, VPN provider, or hosting provider. It is used to route traffic between your network and the wider internet.
When you visit a website, the website normally sees your public IP address, not the private address of your individual computer or phone.
A private IP address is only meant for use inside a local network. Common private IPv4 ranges include 192.168.x.x, 10.x.x.x, and 172.16.x.x to 172.31.x.x.
These addresses are not normally reachable directly from the public internet. Many homes and offices use the same private address ranges without conflict because they are separated behind routers.
Most local networks use a router. Your router gives private IP addresses to devices inside your network, while the router itself uses a public IP address when communicating with the internet.
This is why your computer may show a local address like 192.168.1.25, while an IP checker website shows a completely different public IP address.
NAT stands for Network Address Translation. It is a router feature that lets many devices on a private network share one public IP address when accessing the internet.
NAT keeps track of outgoing connections so replies from websites and services are sent back to the correct device inside your local network.