Calculators & Converters
Subnet Calculator
Find the network, broadcast, usable hosts and wildcard for an IPv4 prefix, then split that block into smaller networks.
Free forever.
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How to split a network
- Enter an IPv4 address and its prefix, such as 192.168.0.0 and 16.
- Read the network, mask, range and host count. A host address is placed inside its network.
- Set a longer prefix to list the smaller networks, then copy or download them.
Questions
How are /31 and /32 counted?
A /31 has two usable addresses and no reserved network or broadcast, which is the point-to-point rule. A /32 is a single host.
Why will a split sometimes be refused?
The new prefix has to be longer than the parent, and the page lists at most 512 networks. Move the new prefix closer to the parent when the list would be larger.
This runs entirely in your browser. Nothing you type is sent to a server.