The /22 subnet
A /22 subnet uses the mask 255.255.252.0 and holds 1,024 addresses, 1,022 of them usable.
A /22 sits between a /16 and a /24: 1,024 addresses, 1,022 usable, mask 255.255.252.0. It is a common size for a large flat segment or for aggregating several /24s into one route.
Summarizing contiguous /24s into a /22 keeps routing tables small. The block still fits inside a single broadcast domain if you want it to, though most designs subnet it further.
Below you can see the exact network, broadcast, and host range for any /22 you enter, calculated instantly in your browser.
Calculate a /22 network
Accepts CIDR (192.0.2.0/24), IP + mask (192.0.2.0 255.255.255.0), or a bare IP (defaults to /24).
11000000.00000000.00000010.0000000011111111.11111111.11111100.00000000Example: 192.0.2.0/22
Taking 192.0.2.0/22 as a worked example, the block breaks down like this:
| Network address | 192.0.0.0 |
|---|---|
| Usable range | 192.0.0.1 - 192.0.3.254 |
| Broadcast address | 192.0.3.255 |
| Total addresses | 1,024 |
| Usable hosts | 1,022 |
| Size | 4 class C blocks |
Frequently asked questions
What is the subnet mask for a /22?
A /22 uses the subnet mask 255.255.252.0. Its wildcard mask, used in access lists, is 0.0.3.255.
How many hosts are in a /22 subnet?
A /22 has 1,024 total addresses and 1,022 usable hosts (the total minus the network and broadcast addresses, except for /31 and /32).
What is a /22 used for?
Standard LAN size. It is equivalent to 4 class C blocks.
How do I calculate a /22 network?
Set the host bits to zero for the network address and to one for the broadcast address. The calculator on this page does it for any /22 block you enter.