CIDR Calculator
Calculate network information from CIDR notation (e.g., 192.168.1.0/24)
CIDR Notation Explained
CIDR (Classless Inter-Domain Routing) notation is a compact method for specifying IP addresses and their associated routing prefix. It combines the network address with a suffix indicating the number of bits in the routing prefix.
What is CIDR?
CIDR (Classless Inter-Domain Routing) is a method for allocating IP addresses and routing Internet Protocol packets. It replaced the older system of classful networking to make IP address allocation more efficient and support better route aggregation.
Common CIDR Blocks
/24 Network (Class C)
256 addresses - Typical for small local networks
/16 Network (Class B)
65,536 addresses - Medium-sized networks
/8 Network (Class A)
16,777,216 addresses - Large enterprise networks
/32 Network (Single Host)
1 address - Individual IP address
/0 Network (Default Route)
All IPv4 addresses - Used for default routing