IPv4
VLSM Planner
Carve a parent block into subnets sized to real host requirements — largest-first, no wasted space. Enter one requirement per line as name:hosts.
Allocation from 10.20.0.0/22244 / 1,024 addrs used (24%)
| Subnet | Needed | CIDR | Mask | Range | Broadcast | Usable |
|---|---|---|---|---|---|---|
| Sales | 120 | 10.20.0.0/25 | 255.255.255.128 | 10.20.0.1 – 10.20.0.126 | 10.20.0.127 | 126 |
| Engineering | 60 | 10.20.0.128/26 | 255.255.255.192 | 10.20.0.129 – 10.20.0.190 | 10.20.0.191 | 62 |
| Voice | 25 | 10.20.0.192/27 | 255.255.255.224 | 10.20.0.193 – 10.20.0.222 | 10.20.0.223 | 30 |
| Servers | 12 | 10.20.0.224/28 | 255.255.255.240 | 10.20.0.225 – 10.20.0.238 | 10.20.0.239 | 14 |
| WAN link | 2 | 10.20.0.240/30 | 255.255.255.252 | 10.20.0.241 – 10.20.0.242 | 10.20.0.243 | 2 |