IP address is a numerical value assigned to a device that uses Internet Protocol for communication. There are two types of IP addresses which are IPV4 and IPV6. IPV4 is 32 bits and IPV6 is 128 bits. Here is a simple vlsm cidr ipv6 subnet calculator to calculate the expanded form of the given IP address and to calculate the prefix and range and the number of subnets. A subnetwork also known as subnet, is a logical and visible subdivision of an IP network. Dividing a network into two or more sub networks is called as subnetting. Enter the correct value for the IPV6 address and click calculate. An example of a correct representation of the IPV6 address is 2001:db8::/32.