Network tools
Calculators for the things you would otherwise work out on paper or look up. Free, no sign-in, and they work without JavaScript.
Subnet calculator
Network, mask, wildcard, broadcast, first and last host and address count for IPv4 and IPv6.
IPv6 subnet calculator
Split a /48 or /56 into /64s, work out EUI-64 from a MAC, find the reverse DNS zone and generate a ULA prefix.
VLSM calculator
Enter segments and device counts and get an address plan with correctly aligned subnets.
The same tools are available inside ipmanager, linked to your subnets – where you can also create the networks straight from a plan.
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