| ビットマスク |
サブネットマスク |
IPアドレス数 |
| 0 |
0.0.0.0 |
4294967296 |
| 1 |
128.0.0.0 |
2147483648 |
| 2 |
192.0.0.0 |
1073741824 |
| 3 |
224.0.0.0 |
536870912 |
| 4 |
240.0.0.0 |
268435456 |
| 5 |
248.0.0.0 |
134217728 |
| 6 |
252.0.0.0 |
67108864 |
| 7 |
254.0.0.0 |
33554432 |
| 8 |
255.0.0.0 |
16777216 |
| 9 |
255.128.0.0 |
8388608 |
| 10 |
255.192.0.0 |
4194304 |
| 11 |
255.224.0.0 |
2097152 |
| 12 |
255.240.0.0 |
1048576 |
| 13 |
255.248.0.0 |
524288 |
| 14 |
255.252.0.0 |
262144 |
| 15 |
255.254.0.0 |
131072 |
| 16 |
255.255.0.0 |
65536 |
| 17 |
255.255.128.0 |
32768 |
| 18 |
255.255.192.0 |
16384 |
| 19 |
255.255.224.0 |
8192 |
| 20 |
255.255.240.0 |
4096 |
| 21 |
255.255.248.0 |
2048 |
| 22 |
255.255.252.0 |
1024 |
| 23 |
255.255.254.0 |
512 |
| 24 |
255.255.255.0 |
256 |
| 25 |
255.255.255.128 |
128 |
| 26 |
255.255.255.192 |
64 |
| 27 |
255.255.255.224 |
32 |
| 28 |
255.255.255.240 |
16 |
| 29 |
255.255.255.248 |
8 |
| 30 |
255.255.255.252 |
4 |
| 31 |
255.255.255.254 |
2 |
| 32 |
255.255.255.255 |
1 |