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IPV4网络掩码对照表
| 序号 | 子网掩码 | CIDR | 总IP数 | 可用IP数 | C网子网数 |
|---|---|---|---|---|---|
| 1 | 255.255.255.255 | /32 | 1 | 1 | 1/256 |
| 2 | 255.255.255.254 | /31 | 2 | 0 | 1/128 |
| 3 | 255.255.255.252 | /30 | 4 | 2 | 1/64 |
| 4 | 255.255.255.248 | /29 | 8 | 6 | 1/32 |
| 5 | 255.255.255.240 | /28 | 16 | 14 | 1/16 |
| 6 | 255.255.255.224 | /27 | 32 | 30 | 1/8 |
| 7 | 255.255.255.192 | /26 | 64 | 62 | 1/4 |
| 8 | 255.255.255.128 | /25 | 128 | 126 | 1/2 |
| 9 | 255.255.255.0 | /24 | 256 | 254 | 1 |
| 10 | 255.255.254.0 | /23 | 512 | 510 | 2 |
| 11 | 255.255.252.0 | /22 | 1024 | 1022 | 4 |
| 12 | 255.255.248.0 | /21 | 2048 | 2046 | 8 |
| 13 | 255.255.240.0 | /20 | 4096 | 4094 | 16 |
| 14 | 255.255.224.0 | /19 | 8192 | 8190 | 32 |
| 15 | 255.255.192.0 | /18 | 16,384 | 16,382 | 64 |
| 16 | 255.255.128.0 | /17 | 32,768 | 32,766 | 128 |
| 17 | 255.255.0.0 | /16 | 65,536 | 65,534 | 256 |
| 18 | 255.254.0.0 | /15 | 131,072 | 131,070 | 512 |
| 19 | 255.252.0.0 | /14 | 262,144 | 262,142 | 1024 |
| 20 | 255.248.0.0 | /13 | 524,288 | 524,286 | 2048 |
| 21 | 255.240.0.0 | /12 | 1,048,576 | 1,048,574 | 4096 |
| 22 | 255.224.0.0 | /11 | 2,097,152 | 2,097,150 | 8192 |
| 23 | 255.192.0.0 | /10 | 4,194,304 | 4,194,302 | 16,384 |
| 24 | 255.128.0.0 | /9 | 8,388,608 | 8,388,606 | 32,768 |
| 25 | 255.0.0.0 | /8 | 16,777,216 | 16,777,214 | 65,536 |
| 26 | 254.0.0.0 | /7 | 33,554,432 | 33,554,430 | 131,072 |
| 27 | 252.0.0.0 | /6 | 67,108,864 | 67,108,862 | 262,144 |
| 28 | 248.0.0.0 | /5 | 134,217,728 | 134,217,726 | 1,048,576 |
| 29 | 240.0.0.0 | /4 | 268,435,456 | 268,435,454 | 2,097,152 |
| 30 | 224.0.0.0 | /3 | 536,870,912 | 536,870,910 | 4,194,304 |
| 31 | 192.0.0.0 | /2 | 1,073,741,824 | 1,073,741,822 | 8,388,608 |
| 32 | 128.0.0.0 | /1 | 2,147,483,648 | 2,147,483,646 | 16,777,216 |
| 33 | 0.0.0.0 | /0 | 4,294,967,296 | 4,294,967,294 | 33,554,432 |