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How do I calculate a subnet?
Enter an IP address and CIDR prefix to instantly see the network address, broadcast, usable host range, total hosts, and subnet mask. Supports IPv4 only. Runs entirely in your browser.
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F.A.Q. — Questions, answered
- What is Subnet Calculator?Enter an IP address and CIDR prefix to instantly see the network address, broadcast, usable host range, total hosts, and subnet mask. Supports IPv4 only. Runs entirely in your browser.
- Is Subnet Calculator free?Yes. Subnet Calculator runs entirely in your browser. No data is uploaded or stored.
- Does Subnet Calculator work offline?Yes. Once loaded, Subnet Calculator works fully offline except for the QR code generator which uses a pinned CDN with SRI.
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