Subnet Mask Lengths / Quick Reference
This is for when you say how many IPs would be in a /20 or /24
Now instead of doing math just remember this table or visit here more often :)
| /32 | 1 IP Address(es) | |
| /31 | 2 IP Address(es) | |
| /30 | 4 IP Address(es) | |
| /29 | 8 IP Address(es) | |
| /28 | 16 IP Address(es) | |
| /27 | 32 IP Address(es) | |
| /26 | 64 IP Address(es) | |
| /25 | 128 IP Address(es) | |
| /24 | 256 IP Address(es) | |
| /23 | 512 IP Address(es) | |
| /22 | 1024 IP Address(es) | |
| /21 | 2048 IP Address(es) | |
| /20 | 4096 IP Address(es) | |
| /19 | 8192 IP Address(es) | |
| /18 | 16384 IP Address(es) | |
| /17 | 32768 IP Address(es) | |
| /16 | 65536 IP Address(es) | |
| /15 | 131072 IP Address(es) | |
| /14 | 262144 IP Address(es) | |
| /13 | 524288 IP Address(es) | |
| /12 | 1048576 IP Address(es) | |
| /11 | 2097152 IP Address(es) | |
| /10 | 4194304 IP Address(es) | |
| /9 | 8388608 IP Address(es) | |
| /8 | 16777216 IP Address(es) | |