pjhtech Tools
Address planning

Subnet Splitter

Divide one IPv4 parent network into equal-size child subnets.

Input

Reset restores the example inputs.

Local calculation · inputs are not sent to a server.

Result

Calculating the example…

Enter the parent IPv4 network and the prefix length wanted for each child. The result lists equal-size subnets that fill the parent. Use those networks in your address plan; an entered host address is first moved to its containing network.

Example: 10.42.16.0/22 split into /24s yields 10.42.16.0/24, 10.42.17.0/24, 10.42.18.0/24 and 10.42.19.0/24.

The child prefix cannot be shorter than the parent. An unchanged prefix returns the parent itself. Output is capped at 4096 children. For different host requirements use VLSM instead.

References