CIDR / Subnet Calculator.
Break a CIDR into its network, broadcast, range, masks, and a coloured binary view.
Input
Quick fill
Tap a preset to fill the field. RFC 1918 blocks plus a tiny /30 for quick sanity checks.
Output
Enter a CIDR on the left to see the breakdown.
About this tool.
Type a CIDR like 192.168.1.0/24 to see the network and broadcast addresses, the usable host range, netmask and wildcard, and a bit-level view that splits the network and host portions. Handles edge cases /31 (RFC 3021) and /32. IPv4 only for now.
Privacy.
Runs in your browserInputs and outputs stay in this browser tab. The calculator is pure arithmetic and never makes a network request.
Disclaimer. Provided as-is, with no warranty of any kind. Always check critical results before acting on them. I accept no liability for inaccuracies, bugs, or any loss or damages arising from use of these tools.
Spotted a bug or want to suggest an improvement?Let me know
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