Enter any IPv4 address plus CIDR prefix. Instant network, broadcast, and host range.
Network = IP AND mask. Broadcast = network + host bits set. First/last usable exclude those two, except /31 (both usable, RFC 3021) and /32 (single host).
192.168.1.10/24 → network 192.168.1.0, broadcast 192.168.1.255, usable 192.168.1.1 – 192.168.1.254254. Total 256 minus network and broadcast.
/31 gives 2 usable (point-to-point, no broadcast reserved). /32 is one host address.
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