Networking & IT Tools
Subnetting Planner (VLSM)
Enter a base network, its CIDR prefix, and how many equal subnets you need to see the full breakdown of each resulting subnet.
| Network | Broadcast | Usable range | Usable hosts |
|---|---|---|---|
| 192.168.0.0/26 | 192.168.0.63 | 192.168.0.1 - 192.168.0.62 | 62 |
| 192.168.0.64/26 | 192.168.0.127 | 192.168.0.65 - 192.168.0.126 | 62 |
| 192.168.0.128/26 | 192.168.0.191 | 192.168.0.129 - 192.168.0.190 | 62 |
| 192.168.0.192/26 | 192.168.0.255 | 192.168.0.193 - 192.168.0.254 | 62 |
Splits the base network into equally-sized subnets (rounding up to the next power of two if needed) — a classic VLSM planning step. For unequal-size subnets, you'd allocate the largest requirements first and use this tool per-block.
How to use this tool
- 1Enter the base network address.
- 2Enter the base CIDR prefix.
- 3Enter how many equal subnets you need.
- 4See each subnet's network, broadcast, and usable range.
Frequently asked questions
What if I need unequal-sized subnets?+
This tool splits into equal-sized subnets — for unequal (VLSM) sizing, allocate your largest subnet requirements first, then re-run this tool on the remaining block.