IPv6 subnet calculator

IPv6 CIDR range for ::/100

Calculate the network address, final address, mask, and exact address capacity of any IPv6 CIDR prefix.

Example: 2606:4700::/32

Host bits are normalized to the network address before the range is calculated.

CIDR calculation

Network details for ::/100

The prefix identifies a network with 28 host bits. Every address from the first address through the last address belongs to this range.

CIDR prefix

::/100

Network mask

ffff:ffff:ffff:ffff:ffff:ffff:f000:0

Prefix length

/100

Host bits

28

First address

::

Last address

::15.255.255.255

Total addresses

268435456

Total addresses (human readable)

2^28 addresses (268,435,456; about 268.43 million)

How this range is calculated

  1. 1The /100 prefix keeps the first 100 network bits fixed.
  2. 2Setting all 28 host bits to zero produces ::.
  3. 3Setting those host bits to one produces ::15.255.255.255.

Network address

The normalized prefix base

CIDR notation describes a network, not a single host. If an address with host bits set is entered, this calculator normalizes it to the network base before calculating the range.

Expanded network address

0000:0000:0000:0000:0000:0000:0000:0000

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