CIDR IP Calculator
Calculate IPv4 and IPv6 CIDR network info: network address, broadcast, host range, subnet mask, wildcard, host count. 100% offline.
About CIDR IP Calculator
Calculate IPv4 and IPv6 CIDR network info: network address, broadcast, host range, subnet mask, wildcard, host count. 100% offline. Everything runs locally in your browser — your data never leaves your device.
How to use
- Enter your input in the tool above.
- Adjust any options to your preference.
- Use the Copy or Download buttons to save the result.
- Everything happens locally — your data never leaves your browser.
FAQ
What does this tool do?
Calculate IPv4 and IPv6 CIDR network info: network address, broadcast, host range, subnet mask, wildcard, host count. 100% offline.
Is my data sent to a server?
No. This tool runs 100% in your browser. Nothing is uploaded, tracked, or stored remotely. It works offline as a PWA.
What extra features does this tool have?
Extras: (1) IPv4 CIDR calculation (/0 to /32), (2) IPv6 CIDR calculation (/0 to /128), (3) Network address, broadcast, first/last host, host count, (4) Subnet mask, wildcard mask (IPv4), (5) CIDR to subnet mask and vice versa, (6) Subnet divider — split a /N into multiple /M subnets, (7) Supernet calculator — combine multiple subnets, (8) IP range generator (first..last), (9) IP type detection (private, loopback, multicast, reserved, link-local), (10) Reverse DNS (PTR) name generation, (11) IPv4 ↔ IPv6 mapping (IPv4-mapped IPv6, IPv4-compatible), (12) Copy individual values, export JSON
Does this work offline?
Yes — install as a PWA and use it without network. All processing happens client-side.
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