IPv4 子网查询
子网 Subnets
| CIDR |
子网掩码 |
地址数 |
通配符 |
| /32 |
255.255.255.255 |
1 |
0.0.0.0 |
| /31 |
255.255.255.254 |
2 |
0.0.0.1 |
| /30 |
255.255.255.252 |
4 |
0.0.0.3 |
| /29 |
255.255.255.248 |
8 |
0.0.0.7 |
| /28 |
255.255.255.240 |
16 |
0.0.0.15 |
| /27 |
255.255.255.224 |
32 |
0.0.0.31 |
| /26 |
255.255.255.192 |
64 |
0.0.0.63 |
| /25 |
255.255.255.128 |
128 |
0.0.0.127 |
| /24 |
255.255.255.0 |
256 |
0.0.0.255 |
| /23 |
255.255.254.0 |
512 |
0.0.1.255 |
| /22 |
255.255.252.0 |
1,024 |
0.0.3.255 |
| /21 |
255.255.248.0 |
2,048 |
0.0.7.255 |
| /20 |
255.255.240.0 |
4,096 |
0.0.15.255 |
| /19 |
255.255.224.0 |
8,192 |
0.0.31.255 |
| /18 |
255.255.192.0 |
16,384 |
0.0.63.255 |
| /17 |
255.255.128.0 |
32,768 |
0.0.127.255 |
| /16 |
255.255.0.0 |
65,536 |
0.0.255.255 |
| /15 |
255.254.0.0 |
131,072 |
0.1.255.255 |
| /14 |
255.252.0.0 |
262,144 |
0.3.255.255 |
| /13 |
255.248.0.0 |
524,288 |
0.7.255.255 |
| /12 |
255.240.0.0 |
1,048,576 |
0.15.255.255 |
| /11 |
255.224.0.0 |
2,097,152 |
0.31.255.255 |
| /10 |
255.192.0.0 |
4,194,304 |
0.63.255.255 |
| /9 |
255.128.0.0 |
8,388,608 |
0.127.255.255 |
| /8 |
255.0.0.0 |
16,777,216 |
0.255.255.255 |
| /7 |
254.0.0.0 |
33,554,432 |
1.255.255.255 |
| /6 |
252.0.0.0 |
67,108,864 |
3.255.255.255 |
| /5 |
248.0.0.0 |
134,217,728 |
7.255.255.255 |
| /4 |
240.0.0.0 |
268,435,456 |
15.255.255.255 |
| /3 |
224.0.0.0 |
536,870,912 |
31.255.255.255 |
| /2 |
192.0.0.0 |
1,073,741,824 |
63.255.255.255 |
| /1 |
128.0.0.0 |
2,147,483,648 |
127.255.255.255 |
| /0 |
0.0.0.0 |
4,294,967,296 |
255.255.255.255 |
IP 地址类 IP Address Classes
| Class |
地址段 |
| A |
0.0.0.0 - 127.255.255.255 |
| B |
128.0.0.0 - 191.255.255.255 |
| C |
192.0.0.0 - 223.255.255.255 |
| D |
224.0.0.0 - 239.255.255.255 |
| E |
240.0.0.0 - 255.255.255.255 |
保留(私有)地址段
Class A
10.0.0.0 - 10.255.255.255
Class B
172.16.0.0 - 172.31.255.255
Class C
192.168.0.0 - 192.168.255.255
localhost
127.0.0.0 - 127.255.255.255
zeroconf
169.254.0.0 - 169.254.255.255
内部路由 (
RFC 6598)
100.64.0.0 - 100.127.255.255
十进制到二进制对应表
| 十进制子网掩码 |
对应二进制 |
十进制通配符 |
对应二进制 |
| 255 |
1111 1111 |
0 |
0000 0000 |
| 254 |
1111 1110 |
1 |
0000 0001 |
| 252 |
1111 1100 |
3 |
0000 0011 |
| 248 |
1111 1000 |
7 |
0000 0111 |
| 240 |
1111 0000 |
15 |
0000 1111 |
| 224 |
1110 0000 |
31 |
0001 1111 |
| 192 |
1100 0000 |
63 |
0011 1111 |
| 128 |
1000 0000 |
127 |
0111 1111 |
| 0 |
0000 0000 |
255 |
1111 1111 |
术语表
通配符掩码
在用二进制表示的通配符掩码中,0 表示要检查的位,1 表示不需要检查的位。
CIDR
Classless Inter Domain Routing 提供了比传统的 IP 地址类更细致的地址划分。CIDR 标记写法是 /XX