IPv6 subnet calculator

IPv6 CIDR range for fd20:fd90::/30

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 fd20:fd90::/30

The prefix identifies a network with 98 host bits. Every address from the first address through the last address belongs to this range.

CIDR prefix

fd20:fd90::/30

Network mask

ffff:fffc::

Prefix length

/30

Host bits

98

First address

fd20:fd90::

Last address

fd20:fd93:ffff:ffff:ffff:ffff:ffff:ffff

Total addresses

316912650057057350374175801344

Total addresses (human readable)

2^98 addresses (316,912,650,057,057,350,374,175,801,344; about 316.91 octillion)

How this range is calculated

  1. 1The /30 prefix keeps the first 30 network bits fixed.
  2. 2Setting all 98 host bits to zero produces fd20:fd90::.
  3. 3Setting those host bits to one produces fd20:fd93:ffff: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

fd20:fd90:0000:0000:0000:0000:0000:0000

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