DevScratchpad

CIDR Calculator & Subnet Inspector (Offline & Secure)

Calculate IPv4/IPv6 subnets, view CIDR notation, netmasks, broadcast IP, and usable host ranges.

How to use

  1. Enter an IP address and CIDR suffix (e.g. 192.168.1.0/24).
  2. The tool calculates network boundaries, broadcast IP, and total usable addresses.
  3. View detailed bitmask breakdown.

Technical Considerations

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

100% Client-Side Privacy: This tool executes entirely within your browser's runtime environment. No payloads, tokens, or inputs are transmitted to external servers. Safe for offline usage.

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