Subnet / CIDR calculator

IPv4 network, mask, broadcast, and usable hosts from CIDR.

Runs in this tab. The file stays here.

192.168.1.0 → 192.168.1.255254 usable hosts · mask 255.255.255.0

This runs in your browser. Nothing is uploaded.

About Subnet / CIDR calculator

IPv4 CIDR → network, mask, broadcast, usable hosts.

Offline IPv4 math only.

How to use Subnet / CIDR calculator

1Enter CIDR.
2Read network details.

Common questions

IPv6?

Not yet.

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Why this one doesn't upload your file

There is no server to upload to. This page is a static file, and the work happens in your browser using the same graphics and WebAssembly code that renders every other site you visit. Your file is read from disk into memory, processed, and handed back as a download. Once the page has loaded you can disconnect from the network entirely and it keeps working. The longer explanation