Paste a CIDR block like 192.168.1.0/24, or an IP plus a prefix (24) or dotted mask (255.255.255.0). We calculate the network address, broadcast (IPv4), usable host range, wildcard mask, and address counts.

IPv6 works the same way with prefixes such as /64. IPv6 has no broadcast address; the range is the full prefix block.

For /31 and /32 (point-to-point and single host), classic “usable hosts minus network/broadcast” rules don’t apply the same way — we show the addresses in the block instead.