Expand any IPv4 CIDR block into its network, broadcast, netmask, wildcard and usable host range.
Enter a block like `10.0.0.0/24` to get the network and broadcast addresses, the subnet and wildcard masks, the first and last usable host, and the total host count.
Wildcard masks are the inverted form used by Cisco access lists, which is why they are shown alongside the conventional netmask.
Why does a /24 have 254 usable hosts and not 256? The first address identifies the network and the last is the broadcast address, so both are unusable for hosts.
What do /31 and /32 mean? A /32 is a single host route. A /31 is a two-address point-to-point link, where RFC 3021 allows both addresses to be used.