Engineering Tool · Networking
Parse IPv4 CIDR blocks, calculate network bounds and masks, and model subnet divisions for VPC and platform network planning.
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CIDR notation
The prefix length tells you how many bits belong to the network portion. Smaller prefix numbers represent larger address ranges; subnetting borrows more bits to split a parent network into smaller allocations.
Private address planning
For internal VPC design, plan RFC 1918 ranges with enough room for future subnets, Kubernetes pod/service networks and connected environments. Avoid overlapping address space when networks may later be peered or routed together.