Ad
Common subnets
Common use cases
- Plan IP allocations for a new VPC or network
- Verify subnet sizes (/24 = 256 addresses)
- Convert between CIDR and netmask notation
- Calculate AWS/Azure VPC subnets
Frequently asked questions
What does /24 mean?
24 bits of the 32-bit IPv4 address are network bits, leaving 8 bits for hosts. So /24 contains 2⁸ = 256 addresses, with 254 usable hosts (network and broadcast are reserved).
Why does /31 only have 2 hosts?
For point-to-point links (RFC 3021), /31 networks skip the network/broadcast reservation and use both addresses for hosts.