Network, broadcast, usable hosts and the wildcard mask — what a /26 really means, with free calculators that show every step.
Enter an IP and CIDR prefix to get the network, broadcast, mask, wildcard, host range and usable host count — the complete subnet breakdown, instantly.
Convert a CIDR prefix (/0–/32) to its dotted-decimal subnet mask and wildcard mask, and back again — with host counts for each prefix length.
Plan variable-length subnets: enter a base network and the hosts each subnet needs, and get an optimal, non-overlapping allocation — largest-first, no wasted space.
Check whether an IP address falls inside a given CIDR block or subnet — for verifying firewall rules, allowlists and routing without guesswork.
Break down an IPv6 prefix: network address, last address, address count and the number of /64 subnets it contains — for IPv6 network planning.
Convert between subnet masks, CIDR prefixes and wildcard (inverse) masks — the form Cisco ACLs and OSPF use. Includes discontiguous wildcard explanation.
A complete reference table of every IPv4 CIDR prefix (/0–/32) with its subnet mask, wildcard, total addresses and usable hosts — searchable and copyable.
Every tool on ToolJolt is free, runs in your browser and needs no sign-up.