Here are the list of Non-Routable Address Spaces anyone can use:
- 10.0.0.0 - 10.255.255.255
- 172.16.0.0 - 172.31.255.255
- 192.168.0.0 - 192.168.255.255
These private addresses can be used by anyone without approval from a regional Internet registry.
Hope this helps. :D
