IPv6 subnet calculator

IPv6 CIDR range for 2001:db8::/97

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 2001:db8::/97

The prefix identifies a network with 31 host bits. Every address from the first address through the last address belongs to this range.

CIDR prefix

2001:db8::/97

Network mask

ffff:ffff:ffff:ffff:ffff:ffff:8000:0

Prefix length

/97

Host bits

31

First address

2001:db8::

Last address

2001:db8::7fff:ffff

Total addresses

2147483648

Total addresses (human readable)

2^31 addresses (2,147,483,648; about 2.14 billion)

How this range is calculated

  1. 1The /97 prefix keeps the first 97 network bits fixed.
  2. 2Setting all 31 host bits to zero produces 2001:db8::.
  3. 3Setting those host bits to one produces 2001:db8::7fff: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

2001:0db8:0000:0000:0000:0000:0000:0000

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