CIDR Calculator
Calculates total addresses and usable hosts for a given CIDR prefix.
Lilu Baba's CIDR Calculator quickly shows how many addresses and usable hosts a given CIDR prefix provides, without needing a specific IP address.
How to use this tool
- Enter a CIDR prefix from 0 to 32.
- Subnet mask, total addresses and usable hosts update instantly.
FAQ
CIDR Calculator — frequently asked questions
This tool only needs a CIDR prefix to show address counts; our Subnet Calculator also needs an IP address to show the actual network and broadcast addresses.
A /24 prefix provides 256 total addresses (254 usable hosts).