IPv6 subnet calculator

IPv6 CIDR range for fe80::/99

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 fe80::/99

The prefix identifies a network with 29 host bits. Every address from the first address through the last address belongs to this range.

CIDR prefix

fe80::/99

Network mask

ffff:ffff:ffff:ffff:ffff:ffff:e000:0

Prefix length

/99

Host bits

29

First address

fe80::

Last address

fe80::1fff:ffff

Total addresses

536870912

Total addresses (human readable)

2^29 addresses (536,870,912; about 536.87 million)

How this range is calculated

  1. 1The /99 prefix keeps the first 99 network bits fixed.
  2. 2Setting all 29 host bits to zero produces fe80::.
  3. 3Setting those host bits to one produces fe80::1fff: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

fe80:0000:0000:0000:0000:0000:0000:0000

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