IPv6 subnet calculator

IPv6 CIDR range for a76b:2d91::/33

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 a76b:2d91::/33

The prefix identifies a network with 95 host bits. Every address from the first address through the last address belongs to this range.

CIDR prefix

a76b:2d91::/33

Network mask

ffff:ffff:8000::

Prefix length

/33

Host bits

95

First address

a76b:2d91::

Last address

a76b:2d91:7fff:ffff:ffff:ffff:ffff:ffff

Total addresses

39614081257132168796771975168

Total addresses (human readable)

2^95 addresses (39,614,081,257,132,168,796,771,975,168; about 39.61 octillion)

How this range is calculated

  1. 1The /33 prefix keeps the first 33 network bits fixed.
  2. 2Setting all 95 host bits to zero produces a76b:2d91::.
  3. 3Setting those host bits to one produces a76b:2d91:7fff: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

a76b:2d91:0000:0000:0000:0000:0000:0000

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