VLSM planner
Split one network into right-sized subnets for each team or link.
Runs on your device · nothing is uploaded
How to use it
- Enter the network you have been given, in CIDR form (for example
192.168.10.0/24). - List each subnet you need on its own line: a name, then the number of hosts.
- Press Plan subnets. The planner gives the biggest subnet the first block, which avoids wasted gaps.
Good to know
Each subnet loses two addresses: the network address and the broadcast address. A point-to-point router link needs 2 hosts, so it gets a /30. Leave spare room for growth: a team of 50 today is often 70 next year.