A LITTLE HELP FOR YOUR NEXT TASK
IPv4 & IPv6 CIDR Calculator
Calculate network boundaries, address counts and child subnets.
Private by design
Your inputs stay on your device and are not sent to our servers. Optional usage analytics does not receive your files or tool inputs.
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How to use IPv4 & IPv6 CIDR Calculator
- Enter an IPv4 or IPv6 address with a prefix.
- Choose an optional child prefix.
- Review canonical networks, ranges and subnet boundaries.
What are the limits of IPv4 & IPv6 CIDR Calculator?
No network scanning or address assignment. Up to 256 child subnets. IPv4 /31 and /32 host counts follow point-to-point and single-address conventions. This tool processes inputs in browser memory and makes no upload or lookup request. Clear inputs or close the tab when finished. Exports and clipboard actions are explicit.