The main purpose of managing a supply chain is to ensure the life cycle of a product or service, from reception of raw materials to final distribution. A key factor in achieving the goals of the organization lies in the timing of its processes, since variations in demand can lead to late deliveries, cancellation of orders, and increased reliance on inventory. Therefore, this paper proposes a model that determines the optimal amount to be produced, taking into account the various stages of the supply chain, many of which have not been considered in original models. This model involves reducing inventory overruns and the opportunity cost of using the Excel spreadsheet.