IPv4 Subnet Mask Calculator

Enter an IPv4 address, mask, prefix, host count or subnet split and get the exact network, host range, wildcard mask and CIDR data instantly.

Network address + mask/prefix

Enter an IPv4 address, mask, prefix, host count or subnet split and get the exact network, host range, wildcard mask and CIDR data instantly.

IPv4 + subnet mask

Subnet details

Network address

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Host range

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Broadcast address

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Wildcard mask

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CIDR prefix

—

Subnet mask
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First usable host
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Last usable host
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Total IP addresses
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Usable hosts
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Block size / increment
—
Class & scope
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Generated subnets

# CIDR Network Host range Broadcast

No subnets to display yet.

What this tool does

The IPv4 subnet mask calculator derives key network properties from an IPv4 address, mask, or CIDR prefix. Depending on the input, it can show the network address, broadcast, host range, and host count.

How to use the tool

  1. Enter an IPv4 address together with a mask or prefix.
  2. Choose a calculation mode for host counts or subnet splitting when needed.
  3. Review the network and host values and any input notes shown by the tool.

Useful applications

  • Planning address ranges for a local network.
  • Checking CIDR notation and subnet masks in a network configuration.
  • Finding network, broadcast, and usable host addresses for documentation.

Notes and limitations

  • The calculation covers IPv4 networks; IPv6 prefixes are not processed by this tool.
  • Private and public ranges are calculated but not checked for actual use or reachability.

Frequently asked questions

What does a CIDR prefix describe?

The prefix states how many bits of an IPv4 address belong to the network portion. The remaining bits identify addresses within that network.

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