Economic Order Quantity Technique
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Economic Order Quantity is a formula-based inventory management technique that calculates the optimal quantity of stock a business should order at one time to minimize its total inventory costs. It balances two competing cost pressures: the cost of ordering too frequently and the cost of holding too much stock at once.
In depth
The EOQ formula takes into account three variables: the annual demand for the product, the cost of placing a single order, and the annual holding cost per unit. By finding the order quantity that minimizes the combined total of ordering and holding costs, EOQ helps businesses avoid the inefficiencies of both over-ordering (which ties up cash and increases storage costs) and under-ordering (which leads to stockouts, rush orders, and production delays). The resulting quantity represents the most cost-efficient replenishment size given the specific cost parameters of the business.
While EOQ is a useful starting point for inventory planning, it works best under a set of idealized assumptions, including constant and predictable demand, fixed order and holding costs, and instantaneous replenishment. In reality, demand fluctuates, lead times vary, and costs change, which means EOQ should be used as a guide rather than a rigid rule. Many businesses adapt the model by incorporating safety stock buffers, seasonal demand adjustments, and supplier minimum order requirements to make it practical in real-world conditions. Despite its simplicity, EOQ remains one of the most foundational tools in supply chain and operations management.