/11 Subnet Mask: 255.224.0.0
A /11 prefix fixes the first 11 bits of the address as the network, leaving 21 bits for hosts. That gives 2,097,152 addresses, of which 2,097,150 can be assigned to hosts.
| CIDR notation | /11 |
| Subnet mask | 255.224.0.0 |
| Wildcard mask | 0.31.255.255 |
| Binary mask | 11111111.11100000.00000000.00000000 |
| Hex mask | 0xFFE00000 |
| Total addresses | 2,097,152 |
| Usable hosts | 2,097,150 |
Example: 10.0.0.0/11
- Network address: 10.0.0.0
- First usable host: 10.0.0.1
- Last usable host: 10.31.255.254
- Broadcast address: 10.31.255.255
When to use a /11 subnet
Very large private networks. 10.0.0.0/8 is the largest private IPv4 range defined by RFC 1918.
- 8 /11 subnets fit in a /8.
Frequently Asked Questions
What is the subnet mask for /11?
The subnet mask for /11 is 255.224.0.0, and its wildcard (inverse) mask is 0.31.255.255.
How many hosts are in a /11?
A /11 contains 2,097,152 addresses. Subtracting the network and broadcast addresses leaves 2,097,150 usable hosts.