Free to use · Client-side calculation · Built for engineers

The CIDR toolkit built for
network engineers & cloud teams

Calculate, split, visualize and export subnets for AWS, Azure, GCP and on-prem. IPv4, IPv6, VLSM, Terraform — all in one place.

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Prefix length /16
Network
10.0.0.0
Broadcast
10.0.255.255
Usable hosts
65,534
Subnet mask
255.255.0.0
Wildcard
0.0.255.255
First usable
10.0.0.1
Last usable
10.0.255.254
Type
Private
Cloud-aware for every major provider
AWS VPCAzure VNetGoogle CloudOracle CloudKubernetes
Everything you need

One toolkit, every subnet workflow

Stop juggling four different calculators. Everything from quick math to Terraform export lives in one place.

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Free, no signup, no tracking. Just open the calculator and start.

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