โฑ๏ธ Productivity
IP Subnet Calculator
A CIDR prefix such as /24 means the first 24 bits are the network, leaving 8 bits for hosts โ 256 addresses, of which two are reserved for the network and broadcast addresses. Halving the host bits doubles the number of subnets.
How it works
First octet
Second octet
Third octet
Fourth octet
CIDR prefix
Subnet mask
Network address
Broadcast address
First usable host
Last usable host
Total addresses
Usable hosts
Wildcard mask
Frequently asked questions
How do I use the IP Subnet Calculator?
Fill in the fields above โ the result recalculates instantly as you type. Everything runs in your browser, so the values you enter are never collected or stored.
Is this calculator free?
Yes. It is completely free, requires no account, and works on phones, tablets and desktops.