ClassPrivate Address Range
 
A10.0.0.0 to 10.255.255.25
B172.16.0.0 to 172.31.255.255
C192.168.0.0 to 192.168.255.255


here is my list i use whenever i want to find out which are the private network ip addresses ranges so i can configure my router for my private network. you mainly have three, class a, class b and class c

i usually use the class C most of the time, i think its the most commonly used private ip.