IPv4 Subnet Splitter
Divide an IPv4 network into equal-size subnets by target prefix, number of subnets, or required hosts per subnet. Equal-size splitting only — not variable-length (VLSM) allocation.
This tool handles input and primary processing in your browser and is designed not to send the input to QuickKit’s server.
How it works
Choose how to size the subnets: an explicit new prefix, a number of subnets from 1 to 1,024 (rounded up to the next power of two), or the usable hosts each subnet must hold (which reserves the network and broadcast addresses). All child subnets are the same size: this is equal-size splitting, not true VLSM. It is listed under the VLSM keyword because equal splitting is the usual first step, but it does not allocate differently sized subnets from one list of host requirements — for mixed sizes, split the leftover block again at each size. Output is capped at 1,024 subnets in every mode.