IPv6 Subnetting Calculator

Input an IPv6 address and the subnet size in slash notation:

Compressed Address:
Expanded Address:
Number of /64s:

Select a number of subnets or a subnet size to divide the above into:

subnets or

This calculator can be used for IPv6 in the same way VLSM is used to plan an IPv4 network.
Remember, the size of IPv6 can be huge. This calculator can crash your browser if you attempt to have it calculate billions of subnets!
Because of this, only the first 999 subnets are displayed.

Use the above calculator to plan your IPv6 networks. Because of the huge size of IPv6, we do not care about the number of hosts in a network. Remember, that the smallest recommended subnet is a /64.