SubnetKit

Calculate subnet masks, network addresses, broadcast addresses, and host ranges

Calculate IPv6 subnets and network prefixes

Variable Length Subnet Mask calculator for splitting networks into smaller subnets

Aggregate multiple networks into supernets for route summarization

Design VLSM networks with drag-and-drop planning

Convert IP address ranges (start-end) into minimal CIDR blocks

Optimize mixed IP addresses, CIDR blocks, and ranges into minimal CIDR prefixes

Split a network into N equal child subnets or to a target prefix length

Find available subnets in pools using first-fit or best-fit algorithms

List unallocated IP blocks in CIDR pools by prefix length

Break CIDR blocks into smaller uniform subnets (e.g., split into /24s)

Compare CIDR lists to show added, removed, and unchanged blocks

Allocate subnets into network pools using first-fit or best-fit algorithms

Check if IP addresses align to CIDR prefix boundaries

Convert between CIDR, subnet masks, and wildcard masks with ACL rule generation