Little's Law

Output: Press calculate

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Formula:L = λW

Introduction to Little's Law

Little's Law is a widely recognized theorem in queuing theory. It relates the number of items ( L ) in a queuing system to the average arrival rate ( λ ) and the average time ( W ) an item spends in the system. Mathematically, it's expressed as L = λW. It is applicable for stable systems where the average number in the system or in the queue, average arrival rate, and average waiting time remain constant over time.

Parameter usage:


Data validation

L, and W should be greater or equal to zero and λ should be greater than zero.


The formula is crucial in designing and understanding processes and systems that involve waiting lines or queues, such as customer service desks, manufacturing processes, and computer networks.

Tags: Operational Research, Queueing Theory, Little S Law