What are some edge cases for CIDR Calculator?

/31 and /32 point-to-point subnets.

Is this CIDR Calculator safe for sensitive data & credentials?

Yes, 100%. All processing runs client-side in your local browser memory. No text, tokens, payloads, or logs are ever transmitted to any remote server or analytics engine.

Can I use CIDR Calculator offline without internet?

Yes. Because this tool runs strictly on client-side JavaScript with zero external API calls, once the web application is loaded in your browser it will continue working offline.

How does URL state sharing work?

When you click Share Payload, your state is encoded directly into a URL hash fragment (#data=...) without storing anything on a database server.

CIDR Calculator & IPv4 Subnet Mask Visualizer — DevScratchpad

Calculate IP subnets, CIDR ranges, network address, broadcast address, and usable host capacity online.

How to use

Enter an IP address with subnet mask or CIDR prefix (e.g. 192.168.1.0/24).
The tool calculates network boundaries, broadcast IP, and total usable addresses.
View detailed bitmask breakdown.

Important Considerations

/31 and /32 point-to-point subnets.

Privacy Notice: This tool is strictly client-side. All processing runs in your local browser memory using JavaScript. No text, tokens, payloads, or logs are ever transmitted to any remote server or analytics engine. You can even use this tool completely offline.

CIDR Calculator

IP & CIDR Calculator (Offline & Secure)

How to use

Important Considerations

Keyboard Shortcuts

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