What is a /22 subnet? 1,024 IPs and why it's the office-network sweet spot

A /22 is the practical ceiling for a single broadcast domain in 2026. Bigger subnets (/21, /20) start to suffer from broadcast chatter on anything but the most carefully designed networks. For a growing office or a cloud subnet that needs headroom, /22 hits the sweet spot between address abundance and network hygiene.

A /22 subnet, written as 255.255.252.0, provides 1,024 total addresses with 1,022 usable for hosts. It's increasingly popular as the default subnet size for medium business networks, accommodating not just computers and phones but also the explosion of IoT devices, cameras, sensors, and guest Wi-Fi.

By TechCompare ยท Updated

CIDR
/22
Class B
Total addresses
1,024
1,022 usable for hosts
Network size
Medium Networks
Larger deployments

How this is calculated

With roughly 1,000 usable addresses, a /22 comfortably handles a mid-size office of 200-300 employees, each with a laptop, phone, and maybe a couple of lab or test devices. The broadcast domain at this size is manageable on modern switched networks. A /22 is the most common subnet size for cloud VPC deployments where you want each availability zone to have room for auto-scaling without running out of IPs during a scale-out event.

Verdict

A /22 is the practical ceiling for a single broadcast domain in 2026. Bigger subnets (/21, /20) start to suffer from broadcast chatter on anything but the most carefully designed networks. For a growing office or a cloud subnet that needs headroom, /22 hits the sweet spot between address abundance and network hygiene.

More Subnet scenarios

Frequently asked questions

Is a /22 subnet too big for a small office?
It's more addresses than a 50-person office needs, but it's not harmful. The extra address space costs nothing and means you won't need to renumber if the office grows.