IP Subnet Calculator
IP Subnet Calculator
Calculate network information based on IP address and subnet mask
About IP Addressing
Understanding IP Addresses
An IP address is a unique identifier assigned to each device on a network. IPv4 addresses consist of 32 bits, typically represented as four octets (8 bits each) separated by dots (e.g., 192.168.1.1).
Subnet Masks
A subnet mask is used to divide an IP address into network and host portions. It determines which part of the IP address identifies the network and which part identifies the host. Subnet masks can be represented in dotted decimal (e.g., 255.255.255.0) or CIDR notation (e.g., /24).
CIDR Notation
Classless Inter-Domain Routing (CIDR) notation is a compact method for specifying IP addresses and their subnet masks. It consists of the IP address followed by a slash and the number of bits in the network portion (e.g., 192.168.1.0/24).
Common Subnet Masks
| CIDR | Subnet Mask | Usable Hosts |
|---|---|---|
| /24 | 255.255.255.0 | 254 |
| /25 | 255.255.255.128 | 126 |
| /26 | 255.255.255.192 | 62 |
| /27 | 255.255.255.224 | 30 |
| /28 | 255.255.255.240 | 14 |
| /29 | 255.255.255.248 | 6 |
| /30 | 255.255.255.252 | 2 |