IPv6 subnet calculator

IPv6 CIDR range for 2a01:111:f400::/49

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 2a01:111:f400::/49

The prefix identifies a network with 79 host bits. Every address from the first address through the last address belongs to this range.

CIDR prefix

2a01:111:f400::/49

Network mask

ffff:ffff:ffff:8000::

Prefix length

/49

Host bits

79

First address

2a01:111:f400::

Last address

2a01:111:f400:7fff:ffff:ffff:ffff:ffff

Total addresses

604462909807314587353088

Total addresses (human readable)

2^79 addresses (604,462,909,807,314,587,353,088; about 604.46 sextillion)

How this range is calculated

  1. 1The /49 prefix keeps the first 49 network bits fixed.
  2. 2Setting all 79 host bits to zero produces 2a01:111:f400::.
  3. 3Setting those host bits to one produces 2a01:111:f400:7fff: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

2a01:0111:f400:0000:0000:0000:0000:0000

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