/26 Subnet Mask

A /26 subnet mask is 255.255.255.192. It has 64 addresses, 62 usable hosts and the wildcard mask 0.0.0.63.

CIDR prefix/26
Subnet mask255.255.255.192
Wildcard mask0.0.0.63
Binary mask11111111.11111111.11111111.11000000
Total addresses64
Usable hosts62
Block size64 (fourth octet)

Example: 192.168.1.0/26

Network address192.168.1.0
First usable host192.168.1.1
Last usable host192.168.1.62
Broadcast address192.168.1.63

Where /26 subnets start

/26 networks start on multiples of 64 in the fourth octet (0, 64, 128, 192, …). A /24 holds 4 /26 subnets, and a /16 holds 1,024.

How to calculate a /26 subnet

  1. Host bits: 32 − 26 = 6.
  2. Total addresses: 26 = 64.
  3. Usable hosts: 64 − 2 = 62, because the network and broadcast addresses can't be assigned to hosts.
  4. Subnet mask: 26 one-bits followed by 6 zero-bits. The fourth octet is 192 (256 − 64), which gives 255.255.255.192.
  5. Wildcard mask: 255.255.255.255 − 255.255.255.192 = 0.0.0.63.

When to use a /26

A /26 splits a /24 into four subnets of 62 usable hosts each.

Updated . Calculate any network with the subnet calculator, or compare all prefixes in the subnet cheat sheet.