IPv6 subnet calculator

IPv6 CIDR range for 2607:fb90::/28

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 2607:fb90::/28

The prefix identifies a network with 100 host bits. Every address from the first address through the last address belongs to this range.

CIDR prefix

2607:fb90::/28

Network mask

ffff:fff0::

Prefix length

/28

Host bits

100

First address

2607:fb90::

Last address

2607:fb9f:ffff:ffff:ffff:ffff:ffff:ffff

Total addresses

1267650600228229401496703205376

Total addresses (human readable)

2^100 addresses (1,267,650,600,228,229,401,496,703,205,376; about 1.26 nonillion)

How this range is calculated

  1. 1The /28 prefix keeps the first 28 network bits fixed.
  2. 2Setting all 100 host bits to zero produces 2607:fb90::.
  3. 3Setting those host bits to one produces 2607:fb9f: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

2607:fb90:0000:0000:0000:0000:0000:0000

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