Subnet Calculator

Enter an IPv4 address and dotted-decimal subnet mask to calculate network details.

Subnet Calculator tool

Example: IP 192.168.1.10 with mask 255.255.255.0

Result will appear here.
Metric Value

Privacy: calculations run locally in your browser. No network data is stored or transmitted.

The subnet mask is converted to a binary prefix, then used to calculate:

  • Network address
  • Broadcast address
  • Wildcard mask
  • Usable host range

Examples

  • 192.168.1.10 + 255.255.255.0 → network 192.168.1.0
  • 10.0.5.20 + 255.255.0.0 → prefix /16
  • 172.16.8.1 + 255.255.240.0 → prefix /20

FAQ

  • What input does this subnet calculator use?

    It uses an IPv4 address and a subnet mask in dotted-decimal form such as 255.255.255.0.

  • What does it calculate?

    It calculates the network address, broadcast address, wildcard mask, CIDR prefix, and usable host range.

  • Does it validate the subnet mask?

    Yes. It checks that the mask is a valid contiguous IPv4 subnet mask.

  • Is my data stored?

    No. The calculation runs locally in your browser.

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