IPv6 subnet calculator

IPv6 CIDR range for fe80::/54

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::/54

The prefix identifies a network with 74 host bits. Every address from the first address through the last address belongs to this range.

CIDR prefix

fe80::/54

Network mask

ffff:ffff:ffff:fc00::

Prefix length

/54

Host bits

74

First address

fe80::

Last address

fe80::3ff:ffff:ffff:ffff:ffff

Total addresses

18889465931478580854784

Total addresses (human readable)

2^74 addresses (18,889,465,931,478,580,854,784; about 18.88 sextillion)

How this range is calculated

  1. 1The /54 prefix keeps the first 54 network bits fixed.
  2. 2Setting all 74 host bits to zero produces fe80::.
  3. 3Setting those host bits to one produces fe80::3ff: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

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

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