CIDR is the short for Classless Inter-Domain Routing, an IP addressing scheme that replaces the older system based on classes A, B, and C. A single IP address can be used to designate many unique IP addresses with CIDR. A CIDR IP address looks like a normal IP address except that it ends with a slash followed by a number, called the IP network prefix. CIDR addresses reduce the size of routing tables and make more IP addresses available within organizations. Please try out our CIDR calculator below.
ABOUT CIDR - ipv4
The subnet calculator lets you enter a subnet range (CIDR) and see IP address information about that range You can type your range directly in CIDR notation, or use the optional Mask pull-down:
- 74.125.227.0/29
- 74.125.227.0, then select Optional Mask from dropdown
This is a useful feature for service providers and network operator who frequently allocate and work with subnets. CIDR stands for Classless Inter-Domain Routing, and refers to the standard of dividing the entire IP address space into smaller networks of variable size.