| Prefix | Subnet mask | binary form | Total IPs | Usable IPs |
|---|---|---|---|---|
| /32 | 255.255.255.255 | 11111111.11111111.11111111.11111111 | XX | XX |
| /31 | 255.255.255.254 | 11111111.11111111.11111111.11111110 | 2 | XX |
| /30 | 255.255.255.252 | 11111111.11111111.11111111.11111100 | 4 | 2 |
| /29 | 255.255.255.248 | 11111111.11111111.11111111.11111000 | 8 | 6 |
| /28 | 255.255.255.240 | 11111111.11111111.11111111.11110000 | 16 | 14 |
| /27 | 255.255.255.224 | 11111111.11111111.11111111.11100000 | 32 | 30 |
| /26 | 255.255.255.192 | 11111111.11111111.11111111.11000000 | 64 | 62 |
| /25 | 255.255.255.128 | 11111111.11111111.11111111.10000000 | 128 | 126 |
| /24 | 255.255.255.0 | 11111111.11111111.11111111.00000000 | 256 | 254 |
| /23 | 255.255.254.0 | 11111111.11111111.11111110.00000000 | 512 | 510 |
| /22 | 255.255.252.0 | 11111111.11111111.11111100.00000000 | 1024 | 1022 |
| /21 | 255.255.248.0 | 11111111.11111111.11111000.00000000 | 2048 | 2046 |
| /20 | 255.255.240.0 | 11111111.11111111.11110000.00000000 | 4096 | 4094 |
| /19 | 255.255.224.0 | 11111111.11111111.11100000.00000000 | 8192 | 8190 |
***Subnet mask will begin with series of '1' and end with series of '0', there will not be combination of '1' between '0' and '0' between '1'.
***Total IPs formula 2 to the power of n where n is equal to the number of '1'
***Usable IPs = Total IPs - 2 (2 IPs is due to network and broadcast address)
