IPv6 subnet calculator

IPv6 CIDR range for a800::/5

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 a800::/5

The prefix identifies a network with 123 host bits. Every address from the first address through the last address belongs to this range.

CIDR prefix

a800::/5

Network mask

f800::

Prefix length

/5

Host bits

123

First address

a800::

Last address

afff:ffff:ffff:ffff:ffff:ffff:ffff:ffff

Total addresses

10633823966279326983230456482242756608

Total addresses (human readable)

2^123 addresses (10,633,823,966,279,326,983,230,456,482,242,756,608; about 10.63 undecillion)

How this range is calculated

  1. 1The /5 prefix keeps the first 5 network bits fixed.
  2. 2Setting all 123 host bits to zero produces a800::.
  3. 3Setting those host bits to one produces afff: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

a800:0000:0000:0000:0000:0000:0000:0000

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