IPv6 subnet calculator

IPv6 CIDR range for 2602:fdc9:0:0:140::/74

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 2602:fdc9:0:0:140::/74

The prefix identifies a network with 54 host bits. Every address from the first address through the last address belongs to this range.

CIDR prefix

2602:fdc9:0:0:140::/74

Network mask

ffff:ffff:ffff:ffff:ffc0::

Prefix length

/74

Host bits

54

First address

2602:fdc9:0:0:140::

Last address

2602:fdc9::17f:ffff:ffff:ffff

Total addresses

18014398509481984

Total addresses (human readable)

2^54 addresses (18,014,398,509,481,984; about 18.01 quadrillion)

How this range is calculated

  1. 1The /74 prefix keeps the first 74 network bits fixed.
  2. 2Setting all 54 host bits to zero produces 2602:fdc9:0:0:140::.
  3. 3Setting those host bits to one produces 2602:fdc9::17f: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

2602:fdc9:0000:0000:0140:0000:0000:0000

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