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CIDR Subnetting
CIDR |
Subnet mask |
# of IP addresses |
# of usable IP addresses |
/32 |
255.255.255.255 |
1 |
1 |
/31 |
255.255.255.254 |
2 |
2* |
/30 |
255.255.255.252 |
4 |
2 |
/29 |
255.255.255.248 |
8 |
6 |
/28 |
255.255.255.240 |
16 |
14 |
/27 |
255.255.255.224 |
32 |
30 |
/26 |
255.255.255.192 |
64 |
62 |
/25 |
255.255.255.128 |
128 |
126 |
/24 |
255.255.255.0 |
256 |
254 |
/23 |
255.255.254.0 |
512 |
510 |
/22 |
255.255.252.0 |
1,024 |
1,022 |
/21 |
255.255.248.0 |
2,048 |
2,046 |
/20 |
255.255.240.0 |
4,096 |
4,094 |
/19 |
255.255.224.0 |
8,192 |
8,190 |
/18 |
255.255.192.0 |
16,384 |
16,382 |
/17 |
255.255.128.0 |
32,768 |
32,766 |
/16 |
255.255.0.0 |
65,536 |
65,534 |
/15 |
255.254.0.0 |
131,072 |
131,070 |
/14 |
255.252.0.0 |
262,144 |
262,142 |
/13 |
255.248.0.0 |
524,288 |
524,286 |
/12 |
255.240.0.0 |
1,048,576 |
1,048,574 |
/11 |
255.224.0.0 |
2,097,152 |
2,097,150 |
/10 |
255.192.0.0 |
4,194,304 |
4,194,302 |
/9 |
255.128.0.0 |
8,388,608 |
8,388,606 |
/8 |
255.0.0.0 |
16,777,216 |
16,777,214 |
/7 |
254.0.0.0 |
33,554,432 |
33,554,430 |
/6 |
252.0.0.0 |
67,108,864 |
67,108,862 |
/5 |
248.0.0.0 |
134,217,728 |
134,217,726 |
/4 |
240.0.0.0 |
268,435,456 |
268,435,454 |
/3 |
224.0.0.0 |
536,870,912 |
536,870,910 |
/2 |
192.0.0.0 |
1,073,741,824 |
1,073,741,822 |
/1 |
128.0.0.0 |
2,147,483,648 |
2,147,483,646 |
/0 |
0.0.0.0 |
4,294,967,296 |
4,294,967,294 |