calculate-subnets

CIDR Calculator

Calculates the optimal subnet CIDRs for a network. Uses cidr-calc for IP ranges.

Usage

CLI:

$ pnpm start --needed-blocks=9 --cidr='10.113.0.0/16'

Network IP range: 10.113.0.0 - 10.113.255.255
Total IPs in network: 65,536
Theoretical max IPs per subnet: 7,281

Subnets' CIDR number: /20
Max IPs per subnet: 4,096

CIDR blocks:
Subnet 1: 10.113.0.0/20      (IP range: 10.113.0.0 - 10.113.15.255)
Subnet 2: 10.113.16.0/20     (IP range: 10.113.16.0 - 10.113.31.255)
Subnet 3: 10.113.32.0/20     (IP range: 10.113.32.0 - 10.113.47.255)
Subnet 4: 10.113.48.0/20     (IP range: 10.113.48.0 - 10.113.63.255)
Subnet 5: 10.113.64.0/20     (IP range: 10.113.64.0 - 10.113.79.255)
Subnet 6: 10.113.80.0/20     (IP range: 10.113.80.0 - 10.113.95.255)
Subnet 7: 10.113.96.0/20     (IP range: 10.113.96.0 - 10.113.111.255)
Subnet 8: 10.113.112.0/20    (IP range: 10.113.112.0 - 10.113.127.255)
Subnet 9: 10.113.128.0/20    (IP range: 10.113.128.0 - 10.113.143.255)

Unused IP range: 10.113.144.0 - 10.113.255.255
Number of unused IPs: 28,672
Number of used IPs:   36,864 (56.25%)

JS:

const { cidrBlocks } = uniformlyDistributedSubnets({
  neededBlocks: 9,
  cidr: '10.113.0.0/16',
});

for (const cidrBlock of cidrBlocks) {
  console.log(cidrBlock.toString());
}