EOQ Calculator for Manufacturing

Economic Order Quantity (EOQ) is the optimal order size that minimises the total cost of inventory, including both ordering costs and holding costs. In manufacturing, EOQ helps procurement teams determine exactly how much raw material or components to order at a time to balance the expense of placing frequent orders against the cost of carrying excess inventory.

This calculator uses the classic EOQ formula to determine the ideal order quantity based on your annual demand, cost per order, and annual holding cost per unit. Enter these three values and the tool instantly computes your optimal order quantity, number of orders per year, and total inventory cost. It helps you find the sweet spot between ordering too frequently and overstocking.

Yes, this EOQ calculator is entirely free with no subscription and no limits on the number of calculations. You can run EOQ analyses for multiple raw materials, components, or product lines without any cost. The calculations run in your browser and the live preview updates as you type. To open the full results and PDF report, you enter your name and work email; your contact details, inputs and a results summary are then sent to Perimattic so the team can follow up on your analysis.

You need three inputs: annual demand (total units required per year), ordering cost per order (including paperwork, shipping, receiving, and inspection costs in ₹), and annual holding cost per unit (including storage, insurance, depreciation, and opportunity cost in ₹). For example, if you need 10,000 units/year with ₹500 per order cost and ₹20 holding cost per unit, the calculator determines your optimal order size.

The EOQ calculation is mathematically exact based on your inputs. However, the classic EOQ model assumes constant demand, constant lead time, and no quantity discounts, which may not perfectly reflect real-world conditions. For most manufacturing scenarios, EOQ provides an excellent starting point that can be adjusted based on seasonal demand patterns or supplier constraints.

Yes, once your results are shown you can download a PDF report of your EOQ analysis including the optimal order quantity, reorder frequency, and total cost breakdown. This is useful for procurement documentation, supplier negotiations, and presenting inventory strategies to management. The report helps maintain a record of your ordering decisions.

This tool is ideal for procurement managers, inventory controllers, supply chain professionals, and manufacturing business owners. Whether you are managing raw material purchases for a small workshop or coordinating procurement across multiple factory locations, EOQ analysis helps reduce inventory costs while ensuring adequate stock availability.

The calculator uses the Wilson EOQ formula: EOQ = √(2DS/H), where D is annual demand in units, S is the ordering cost per order in ₹, and H is the annual holding cost per unit in ₹. The total number of orders per year is D/EOQ, and the total inventory cost is the sum of total ordering cost and total holding cost at the optimal quantity.

The calculation is instant once you enter your three input values. Gathering accurate ordering and holding cost data may take 10-15 minutes if you need to compile figures from your accounting or procurement records. Once you have the data, you can quickly run scenarios for different materials or cost assumptions.

EOQ minimises total inventory cost by finding the order size where ordering costs and holding costs are perfectly balanced. For instance, a manufacturer spending ₹2,000 per order with ₹50/unit annual holding cost might find that ordering 400 units at a time instead of 100 reduces total annual inventory cost by 30-40%. This frees up working capital that can be invested elsewhere in the business.