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Subnet Calculator

Enter an IPv4 address with CIDR notation (like 192.168.1.0/24) to instantly calculate the network address, broadcast address, subnet mask, wildcard mask, usable host range, and total number of addresses. Useful for network engineers, sysadmins, or students learning subnetting.

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  • Runs entirely in your browser
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Use Subnet Calculator - free

Frequently asked questions

What is CIDR notation?

Classless Inter-Domain Routing notation expresses an IP address alongside its network prefix length, indicating how many bits define the network portion of the address.

How many usable hosts does a /24 have?

254 usable host addresses - 256 total addresses minus the network address and broadcast address.

Does this support IPv6?

No, this calculator supports IPv4 addressing and CIDR notation only.

Calculate a subnet instantly - free.

Open Subnet Calculator
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  • No upload required
  • No account needed
  • Unlimited use, always free

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