Subnet splitter: divide a network into equal subnets
Enter a network and either how many subnets you want or the prefix of the new subnets. You get the list of equal subnets with their ranges. The number of subnets is always a power of two (2, 4, 8, 16…), so a request for 5 becomes 8.
4 subnets of /26
| # | Network | Range | Broadcast | Usable hosts |
|---|---|---|---|---|
| 1 | 10.0.0.0/26 | 10.0.0.1 – 10.0.0.62 | 10.0.0.63 | 62 |
| 2 | 10.0.0.64/26 | 10.0.0.65 – 10.0.0.126 | 10.0.0.127 | 62 |
| 3 | 10.0.0.128/26 | 10.0.0.129 – 10.0.0.190 | 10.0.0.191 | 62 |
| 4 | 10.0.0.192/26 | 10.0.0.193 – 10.0.0.254 | 10.0.0.255 | 62 |
Questions
How many subnets can I make?
Two to the power of the difference between the new and the old prefix. Splitting a /24 into /26 gives 2^(26 − 24) = 4 subnets of 64 addresses each.
Do I lose addresses by splitting?
A little. Every subnet reserves its own network and broadcast addresses, so four /26 subnets hold 4 × 62 = 248 usable hosts, against 254 in the original /24.
Can the subnets have different sizes?
Not here: this tool makes equal subnets. For different sizes, for example 100 hosts for one team and 20 for another, use the VLSM calculator.