| Number of bits (for CIDR/VLSM) |
Number of addresses available to nodes* |
Mask | Dotted Quad Binary | Comments |
| 32 | 1 | 255.255.255.255 | 11111111.11111111.11111111.11111111 | Single host |
| 31 | 0 | 255.255.255.254 | 11111111.11111111.11111111.11111110 | No hosts |
| 30 | 2 | 255.255.255.252 | 11111111.11111111.11111111.11111100 | |
| 29 | 6 | 255.255.255.248 | 11111111.11111111.11111111.11111000 | |
| 28 | 14 | 255.255.255.240 | 11111111.11111111.11111111.11110000 | |
| 27 | 30 | 255.255.255.224 | 11111111.11111111.11111111.11100000 | |
| 26 | 62 | 255.255.255.192 | 11111111.11111111.11111111.11000000 | |
| 25 | 126 | 255.255.255.128 | 11111111.11111111.11111111.10000000 | |
| 24 | 254 | 255.255.255.0 | 11111111.11111111.11111111.00000000 | "Class C" |
| 23 | 255.255.254.0 | 11111111.11111111.11111110.00000000 | ||
| 22 | 255.255.252.0 | 11111111.11111111.11111100.00000000 | ||
| 21 | 255.255.248.0 | 11111111.11111111.11111000.00000000 | ||
| 20 | 255.255.240.0 | 11111111.11111111.11110000.00000000 | ||
| 19 | 255.255.224.0 | 11111111.11111111.11100000.00000000 | ||
| 18 | 255.255.192.0 | 11111111.11111111.11000000.00000000 | ||
| 17 | 255.255.128.0 | 11111111.11111111.10000000.00000000 | ||
| 16 | 65,000 | 255.255.0.0 | 11111111.11111111.00000000.00000000 | "Class B" |
| 15 | 255.254.0.0 | 11111111.11111110.00000000.00000000 | ||
| 14 | 255.252.0.0 | 11111111.11111100.00000000.00000000 | ||
| 13 | 255.248.0.0 | 11111111.11111000.00000000.00000000 | ||
| 12 | 255.240.0.0 | 11111111.11110000.00000000.00000000 | ||
| 11 | 255.224.0.0 | 11111111.11100000.00000000.00000000 | ||
| 10 | 255.192.0.0 | 11111111.11000000.00000000.00000000 | ||
| 9 | 255.128.0.0 | 11111111.10000000.00000000.00000000 | ||
| 8 | 16,000,000 | 255.0.0.0 | 11111111.00000000.00000000.00000000 | "Class A" |
| 7 | 254.0.0.0 | 11111110.00000000.00000000.00000000 | ||
| 6 | 252.0.0.0 | 11111100.00000000.00000000.00000000 | ||
| 5 | 248.0.0.0 | 11111000.00000000.00000000.00000000 | ||
| 4 | 240.0.0.0 | 11110000.00000000.00000000.00000000 | ||
| 3 | 224.0.0.0 | 11100000.00000000.00000000.00000000 | ||
| 2 | 192.0.0.0 | 11000000.00000000.00000000.00000000 | ||
| 1 | 128.0.0.0 | 10000000.00000000.00000000.00000000 | ||
| 0 | 4G | 0.0.0.0 | 00000000.00000000.00000000.00000000 | Everything |
* This includes an address for the gateway. Thus on a class "C" subnet you can only have 253 nodes.