IPv6 subnet calculator

IPv6 CIDR range for 2a01:7e8:43::/67

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 2a01:7e8:43::/67

The prefix identifies a network with 61 host bits. Every address from the first address through the last address belongs to this range.

CIDR prefix

2a01:7e8:43::/67

Network mask

ffff:ffff:ffff:ffff:e000::

Prefix length

/67

Host bits

61

First address

2a01:7e8:43::

Last address

2a01:7e8:43:0:1fff:ffff:ffff:ffff

Total addresses

2305843009213693952

Total addresses (human readable)

2^61 addresses (2,305,843,009,213,693,952; about 2.3 quintillion)

How this range is calculated

  1. 1The /67 prefix keeps the first 67 network bits fixed.
  2. 2Setting all 61 host bits to zero produces 2a01:7e8:43::.
  3. 3Setting those host bits to one produces 2a01:7e8:43:0:1fff: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

2a01:07e8:0043:0000:0000:0000:0000:0000

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