A prefix also determines how many host addresses exist. This lesson ties the formula to the usable column in the subnet table.
highlighted = computed this step
Why host counts fall out
Once the prefix fixes the network bits, the remaining bits count addresses inside the subnet. The usable column in the table is the arithmetic result, not an independent label.
address bits=32
Count the host bits
There are 32 address bits. A /26 leaves 6 host bits.
32−26=6
Total minus reserved
6 host bits make 64 addresses. 2 cannot be assigned to hosts — the network address, host bits all 0, and the broadcast address, host bits all 1 — leaving 62 usable per row.
64−2=62
Decode it again
For /24, the host side has 8 bits. That gives 256 addresses and 254 usable hosts.
256−2=254
Summary
Host counts come from the number of host bits: total addresses minus the 2 reserved endpoints, the network and broadcast addresses. Address arithmetic only; timing/throughput is not modeled here.