Subnet calculator
Work out the network, broadcast, mask and host range of an IPv4 CIDR block.
In your browser
About this tool
Work out the network, broadcast, mask and host range of an IPv4 CIDR block. It works entirely in your browser, so what you enter stays on your device. It’s free and there’s no account to create.
Questions
Is my data uploaded?
No. This tool runs in your browser, so your text and files never reach our server.
Is this tool free?
Yes. It’s free to use with no sign-up and no limits for normal use.
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