JSON formatter & validator
Format, beautify, validate, and minify JSON online. Pinpoint syntax errors by line and column, sort keys, and copy or download the result.
Subnet calculator
IPv4 subnet calculator for CIDR: network, broadcast, host range, masks, and host count. Split networks into smaller subnets.
How to use Subnet calculator
An IPv4 subnet calculator for CIDR notation. Enter an address like 192.168.1.130/26 or pick a subnet mask.
- Network and broadcast address, usable host range, and host count
- Subnet mask, wildcard mask, and binary mask
- Private, public, or reserved address type, and the reverse DNS zone
- Split the network into smaller subnets
Subnet calculator FAQs
Is Subnet calculator free?
Subnet calculator is a free online tool on ReallyUseful.Tools. No account is required.
Does Subnet calculator run in my browser?
Subnet calculator is designed to run in your browser where supported, so files can stay on your device instead of being uploaded to a server.
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