/22 Subnet Mask

A /22 subnet mask is 255.255.252.0. It has 1,024 addresses, 1,022 usable hosts and the wildcard mask 0.0.3.255.

CIDR prefix/22
Subnet mask255.255.252.0
Wildcard mask0.0.3.255
Binary mask11111111.11111111.11111100.00000000
Total addresses1,024
Usable hosts1,022
Block size4 (third octet)

Example: 192.168.0.0/22

Network address192.168.0.0
First usable host192.168.0.1
Last usable host192.168.3.254
Broadcast address192.168.3.255

Where /22 subnets start

/22 networks start on multiples of 4 in the third octet (0, 4, 8, 12, …). A /16 holds 64 /22 subnets.

How to calculate a /22 subnet

  1. Host bits: 32 − 22 = 10.
  2. Total addresses: 210 = 1,024.
  3. Usable hosts: 1,024 − 2 = 1,022, because the network and broadcast addresses can't be assigned to hosts.
  4. Subnet mask: 22 one-bits followed by 10 zero-bits. The third octet is 252 (256 − 4), which gives 255.255.252.0.
  5. Wildcard mask: 255.255.255.255 − 255.255.252.0 = 0.0.3.255.

When to use a /22

A /22 combines four /24 networks. It suits larger LANs, Wi-Fi networks or cloud subnets that need more than 510 hosts.

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