IPv6 subnet calculator

IPv6 CIDR range for 2603:1017:0:20::/59

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 2603:1017:0:20::/59

The prefix identifies a network with 69 host bits. Every address from the first address through the last address belongs to this range.

CIDR prefix

2603:1017:0:20::/59

Network mask

ffff:ffff:ffff:ffe0::

Prefix length

/59

Host bits

69

First address

2603:1017:0:20::

Last address

2603:1017:0:3f:ffff:ffff:ffff:ffff

Total addresses

590295810358705651712

Total addresses (human readable)

2^69 addresses (590,295,810,358,705,651,712; about 590.29 quintillion)

How this range is calculated

  1. 1The /59 prefix keeps the first 59 network bits fixed.
  2. 2Setting all 69 host bits to zero produces 2603:1017:0:20::.
  3. 3Setting those host bits to one produces 2603:1017:0:3f: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

2603:1017:0000:0020:0000:0000:0000:0000

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