Understanding /24 Subnets (256 Addresses)
The /24 subnet is the most commonly used CIDR block. Learn its properties, how addresses are allocated, and when to use it for servers, containers, and services.
Detailed Explanation
The /24 Subnet: The Workhorse of Networking
A /24 subnet is the most commonly deployed subnet size in both enterprise and cloud networking. With a 24-bit network prefix and 8-bit host portion, it provides exactly 256 IP addresses (254 usable).
Range Details (Example: 10.0.1.0/24)
| Property | Value |
|---|---|
| Network Address | 10.0.1.0 |
| Broadcast Address | 10.0.1.255 |
| Subnet Mask | 255.255.255.0 |
| Wildcard Mask | 0.0.0.255 |
| Total Addresses | 256 |
| Usable Hosts | 254 |
Why /24 Is the Default Choice
The /24 aligns perfectly with the third octet boundary, making addresses easy to read and manage. All addresses share the first three octets (e.g., 10.0.1.x), which simplifies:
- Firewall rules — Allow/deny traffic from 10.0.1.0/24
- Route tables — Single route entry covers all hosts
- DHCP scopes — Clean .1 to .254 range
- Mental math — No complex binary calculation needed
Typical Address Allocation
10.0.1.0 -> Network address (reserved)
10.0.1.1 -> Default gateway / router
10.0.1.2-10 -> Infrastructure (DNS, DHCP, etc.)
10.0.1.11-50 -> Static assignments (servers)
10.0.1.51-200 -> DHCP pool (dynamic clients)
10.0.1.201-254 -> Reserved for future use
10.0.1.255 -> Broadcast address (reserved)
When /24 Is Not Enough
If you need more than 254 hosts in a single broadcast domain, consider a /23 (512 addresses) or /22 (1,024 addresses). For Kubernetes pod networking, /24 per node is standard, but large clusters may need /22 or wider per node.
Use Case
Provisioning a standard application subnet in a VPC, setting up a VLAN for a department or floor in an office building, or allocating a Kubernetes node subnet that needs to host up to 254 pods.