IPv6 subnet calculator

IPv6 CIDR range for 4000::/16

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 4000::/16

The prefix identifies a network with 112 host bits. Every address from the first address through the last address belongs to this range.

CIDR prefix

4000::/16

Network mask

ffff::

Prefix length

/16

Host bits

112

First address

4000::

Last address

4000:ffff:ffff:ffff:ffff:ffff:ffff:ffff

Total addresses

5192296858534827628530496329220096

Total addresses (human readable)

2^112 addresses (5,192,296,858,534,827,628,530,496,329,220,096; about 5.19 decillion)

How this range is calculated

  1. 1The /16 prefix keeps the first 16 network bits fixed.
  2. 2Setting all 112 host bits to zero produces 4000::.
  3. 3Setting those host bits to one produces 4000:ffff:ffff:ffff:ffff:ffff:ffff:ffff.

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

4000:0000:0000:0000:0000:0000:0000:0000

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