Network planning tool
IPv4 subnet calculator
Enter any IPv4 address and CIDR prefix. See the network, mask, usable address range, and number of hosts as you type.
Example: 10.20.30.40
A larger prefix means a smaller subnet.
Subnet results
Calculated in your browser. Your IP address is not sent to Cloudculator.
How to read these results
The network address identifies the subnet. The subnet mask shows which bits belong to the network. A /24 contains 256 total IPv4 addresses, usually 254 usable hosts after reserving the network and broadcast addresses.
A /31 is commonly used for point-to-point links and has two addresses. A /32 identifies one address. Neither has a separate broadcast address in this calculator.
Common subnet sizes
- /24: 256 addresses, usually 254 usable hosts.
- /28: 16 addresses, usually 14 usable hosts.
- /30: 4 addresses, usually 2 usable hosts.
- /31: 2 point-to-point addresses.
- /32: 1 address.