Home / Glossary / CIDR Range
March 19, 2024

CIDR Range

March 19, 2024
Read 2 min

A CIDR range, short for Classless Inter-Domain Routing range, is a method used in the field of computer networking to allocate and manage IP addresses more efficiently. It allows for the efficient allocation of IP addresses by grouping them together in a flexible and scalable manner.


CIDR ranges are used as a way to manage and organize IP addresses. In traditional IP addressing, IP addresses were divided into classes (Class A, B, and C) which had fixed ranges. This led to inefficiencies in IP address allocation, as organizations often ended up with more IP addresses than they actually needed.

With CIDR, IP addresses are not constrained by class boundaries. Instead, CIDR provides a flexible and scalable way of allocating IP addresses. CIDR ranges are expressed in the form of an IP address followed by a slash and a number, such as The number after the slash indicates the number of bits in the network prefix.


CIDR ranges provide several advantages over traditional IP addressing:

  1. Efficient IP address allocation: CIDR allows for the allocation of IP addresses in a more efficient manner, thus reducing IP address exhaustion. It enables organizations to allocate IP addresses based on their actual needs, rather than having to adhere to fixed class-based ranges.
  2. Aggregation and hierarchical addressing: CIDR enables the aggregation of IP addresses into larger blocks, resulting in reduced routing table sizes. This helps in optimizing routing efficiency by reducing the number of routing table entries that routers need to process.
  3. Simplified address management: CIDR simplifies IP address management by allowing for the allocation of IP addresses in a hierarchical manner. This makes it easier to allocate, allocate and manage IP addresses across different networks.


CIDR ranges find wide applications in various areas of information technology. Some notable applications include:

  1. Internet Service Providers (ISPs): ISPs use CIDR ranges to allocate IP addresses to their customers in a more efficient and scalable way. This allows ISPs to efficiently manage their IP address space and accommodate a growing number of customers.
  2. Private networks: CIDR ranges are also used in private networks to allocate IP addresses to devices within an organization. This enables efficient address management and reduces the likelihood of IP address conflicts.
  3. Subnetting: CIDR ranges are used extensively in subnetting, which is the practice of dividing an IP network into smaller subnetworks. Subnetting allows for better network management, security, and improved routing efficiency.


CIDR ranges have revolutionized IP address allocation and management in the field of information technology. By providing a flexible and scalable approach to IP addressing, CIDR allows for efficient allocation, aggregation, and management of IP addresses. This results in reduced IP address exhaustion, optimized routing efficiency, and simplified address management. CIDR ranges are widely used in various domains, including ISPs and private networks, to better manage and allocate IP addresses. With the ongoing expansion of the internet and the increasing number of connected devices, the importance of CIDR ranges in efficiently managing IP addresses cannot be overstated.

Recent Articles

Visit Blog

How cloud call centers help Financial Firms?

Revolutionizing Fintech: Unleashing Success Through Seamless UX/UI Design

Trading Systems: Exploring the Differences

Back to top