10.0.0.0 to 10.255.255.255
172.16.0.0 to 172.31.255.255
192.168.0.0 to 192.168.255.255
Devices with private IP addresses can communicate with other hardware within the same network that also have private IP addresses but not directly with devices with public IP addresses. A router is required for private and public networks to exchange information.
Any IP address inside of a home or business network, like the IP address assigned to one of your personal computers, is a private IP address, not a public IP address.
The IP address that your home or business router receives from your ISP is a public IP address, as are the IP addresses of other devices on the Internet like the servers that host websites.
Note: Another range of private IP addresses is 169.254.0.0 to 169.254.255.255 but is for Automatic Private IP Addressing use only.