Free online tool

IPv4 Subnet Calculator

Enter an IPv4 address and prefix to inspect the complete subnet boundaries.

Network address-
Broadcast address-
Subnet mask-
Wildcard mask-
Usable host range-
Total / usable addresses-

Method

Technical calculation method

The tool uses deterministic browser APIs and standard numeric or data-format rules. Inputs and outputs remain visible so addresses, dimensions, codes, and serialized data can be checked directly.

Network and hardware results follow the selected CIDR, band, pixel, or format values; verify production settings against the target system specification.

Questions

IPv4 Subnet Calculator FAQ

What does a CIDR prefix mean?

The prefix is the number of leading network bits. For example, /24 leaves 8 bits for 256 total IPv4 addresses.

Are network and broadcast addresses usable?

Traditional subnets reserve the first address as network and the last as broadcast. Point-to-point /31 and single-host /32 networks use special rules.

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