IPv6 subnet calculator

IPv6 CIDR range for ::/37

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 ::/37

The prefix identifies a network with 91 host bits. Every address from the first address through the last address belongs to this range.

CIDR prefix

::/37

Network mask

ffff:ffff:f800::

Prefix length

/37

Host bits

91

First address

::

Last address

::7ff:ffff:ffff:ffff:ffff:ffff

Total addresses

2475880078570760549798248448

Total addresses (human readable)

2^91 addresses (2,475,880,078,570,760,549,798,248,448; about 2.47 octillion)

How this range is calculated

  1. 1The /37 prefix keeps the first 37 network bits fixed.
  2. 2Setting all 91 host bits to zero produces ::.
  3. 3Setting those host bits to one produces ::7ff: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

0000:0000:0000:0000:0000:0000:0000:0000

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