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IsekaiKit › Tools

Subnet calculator

Type an address such as 192.168.1.10/24, 10.0.0.1 255.255.0.0 or 2001:db8::/48.

Split into subnets

New prefix

How to use it

Enter an IPv4 address with a prefix (/24) or a netmask (255.255.255.0), or pick the prefix from the list. You get the network and broadcast addresses, the first and last usable host, how many hosts fit, the wildcard mask for ACLs and the address type. Choose a longer prefix under Split into subnets to carve the block into equal pieces.

Quick CIDR reference

IPv6

Type an IPv6 address with a prefix to see the compressed and expanded forms, the network, the full address range and the address type. LANs normally use /64, and sites often get a /48 or /56.

Is my data safe?

Yes. Everything runs in your browser. Nothing you paste here is sent to any server.

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