How many usable host addresses are available in a /26 subnet?

How many usable host addresses are available in a /26 subnet?

• A. 60 usable hosts
• B. 61 usable hosts
• C. 64 usable hosts
• D. 62 usable hosts

Answer: (D)

In IPv4 subnetting, the number of addresses in a subnet is 2^(32 - prefix length). For a /26, that’s 2^(32-26) = 64 total addresses. The network address (the first) and the broadcast address (the last) aren’t usable for hosts, so you subtract 2. That leaves 62 usable host addresses. For example, in 192.168.1.0/26, usable hosts range from 192.168.1.1 to 192.168.1.62, with 192.168.1.0 as the network address and 192.168.1.63 as the broadcast.

In IPv4 subnetting, the number of addresses in a subnet is 2^(32 - prefix length). For a /26, that’s 2^(32-26) = 64 total addresses. The network address (the first) and the broadcast address (the last) aren’t usable for hosts, so you subtract 2. That leaves 62 usable host addresses. For example, in 192.168.1.0/26, usable hosts range from 192.168.1.1 to 192.168.1.62, with 192.168.1.0 as the network address and 192.168.1.63 as the broadcast.