Why it helps
This calculator helps you read subnet boundaries, understand the size of a range and move through neighboring IPv4 blocks when debugging firewall rules, inventory or access scope.
Network Math
Open homepage tool
IPv4 Subnet Calculator
Convert prefixes and CIDR notation into usable IPv4 ranges and inspect addresses inside each subnet.
Networks
IP Subnet Browser
Search by subnet prefix like 216.73.217
or CIDR notation like 10.0.0.0/16 and 2001:db8::/48.
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