What this tool can and cannot do
Runs entirely in your browser. IPv4 only – use the CIDR calculator for IPv6 prefixes.
Data sources: None – runs in your browser
Understanding the results
Usable hosts excludes the network and broadcast addresses, except for /31 (point-to-point links, 2 usable) and /32 (a single host).
Troubleshooting
- You can enter the mask in either format: 10.0.0.5/22 or 10.0.0.5 255.255.252.0.
Frequently asked questions
What does /24 mean?
The first 24 bits identify the network, leaving 8 bits (256 addresses, 254 usable) for hosts. Its mask is 255.255.255.0.