EOQ — Economic Order Quantity
🏭 Industrial · Optimal order quantity and total annual inventory cost
Inventory management involves two opposing cost pressures: ordering frequently incurs a fixed order cost each time (shipping, processing, setup), while rare, large orders lead to a high holding cost (storage, capital tied up, spoilage risk).
The classic EOQ (Economic Order Quantity) model published by Ford W. Harris in 1913 mathematically derives the optimal order quantity that minimizes the sum of these two costs. The model’s elegant result is: at the optimal point, the total annual ordering cost is exactly equal to the total annual holding cost — this tool’s verification tests also check this property.
Assumptions and limitations of the model: the classic EOQ assumes demand is constant and known with certainty, lead time is zero, and there are no quantity discounts. If real-world demand is uncertain, a safety stock must also be calculated — this tool does not cover that.
This tool's calculation logic has been checked against a hand-computed numerical verification test. Test source: src/lib/calc/eoq.test.ts.
- [12] Harris, Ford W.. "How Many Parts to Make at Once". Factory: The Magazine of Management, 10(2), 135--136. 1913. (EOQ modelinin ilk tanımı; yeniden basım: Operations Research 38(6), 1990) ↗
EOQ — Economic Order Quantity — EngineersLab calc card
Formula: Q* = √(2DS/H)
Sources: [12] How Many Parts to Make at Once
Tool version: 1.0.0 · Date:
Source URL: https://engineerslab.com.tr/en/araclar/eoq
Results are for educational and preliminary-sizing purposes; final engineering design decisions must reference the relevant standards and a licensed engineer's approval.