DevOps LoungeCIDR and subnet calculator
Type a range like 10.0.0.0/16. See the network, mask, usable hosts and broadcast, split it into smaller subnets, and check whether an address belongs to it.
How it works
- Usable hostsEvery range loses two addresses, the network and the broadcast, except /31 and /32. Cloud providers often reserve a few more in each subnet.
- Planning a VPCStart with a /16 and split it into /24s: one per subnet and zone, with room to grow.
Questions
What does /24 mean?
The first 24 bits are the network, leaving 8 bits, or 256 addresses, for hosts.
Does it handle IPv6?
Not yet. It covers IPv4, which is what most subnet planning still uses.
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