Articles on: Inventory Replenishment

Fixed Order Quantity Model

The Fixed Quantity Order Model, also known as the Fixed Order Quantity (FOQ) or Economic Order Quantity (EOQ) model, is a time-tested inventory management strategy that offers a straightforward approach to replenishing stock. In this section, we'll dive into the core principles of this model, helping you establish a strong foundation for its application in your inventory management processes.

Key Concepts

To effectively understand and implement the Fixed Quantity Order Model, it's essential to grasp the following key concepts:

Order Quantity: In this model, you determine a fixed amount of inventory that you will order whenever your inventory level drops to a certain threshold. This fixed quantity is referred to as the "reorder quantity."

Reorder Point: The "reorder point" is the predetermined inventory level at which you decide to place a new order. When your inventory reaches or falls below this point, you initiate the replenishment process.

Economic Order Quantity (EOQ): The EOQ is a crucial formula used in this model to calculate the optimal reorder quantity that minimizes total inventory costs. It takes into account factors such as holding costs and ordering costs.

The Workflow

Here's a simplified explanation of how the Fixed Quantity Order Model works:

You begin by setting the reorder quantity that is appropriate for your business and the specific products you manage.

As you monitor your inventory levels, you continuously compare them to the reorder point. When the inventory reaches or falls below the reorder point, you initiate an order to replenish stock.

The reorder quantity is fixed, meaning that you consistently order the same amount each time. This simplicity streamlines the ordering process.

After placing the order, you await the delivery of the inventory, and the cycle repeats as your stock is used and your inventory levels drop.

Fixed order quantity inventory management model


This model offers several benefits, including:

Cost Optimization: It minimizes total inventory costs, reducing both holding and ordering costs.

Consistency: Maintains consistent inventory levels, meeting customer demand without stockouts or overstock.

Simplified Operations: Fixed quantity ordering is straightforward and easy to manage. This simplicity can be especially advantageous for businesses with limited resources and inventory management expertise.


Address the challenges of the Fixed Quantity Order Model:

Variable Demand and Lead Times: It may struggle with fluctuations in demand or unpredictable supplier lead times.

Which Businesses Are Best Suited?

The Fixed Quantity Order Model is not one-size-fits-all. Let's identify which businesses can make the most of this model:

Steady Demand Patterns: Businesses with consistent and predictable demand patterns will find this model highly effective. It simplifies inventory management when you can rely on stable demand.

Efficient Suppliers: If your suppliers consistently meet lead times and provide reliability, the Fixed Quantity Order Model can excel in optimizing your inventory levels.

Higher-priced, critical, or important items: The FOQ model ensures that the right amount of inventory is maintained to meet demand without excessive holding costs, reducing the risk of stockouts for critical items

Applying the Fixed Order Quantity Model in Assisty

Implementing the Fixed Order Quantity Model in your inventory management strategy can be a game-changer for your business. Assisty, our advanced inventory management system, complements this model perfectly and enhances its effectiveness. In this section, we'll explore how to apply the Fixed Order Quantity Model in Assisty, with a special focus on two critical parameters: reorder point and fixed reorder quantity.

Reorder Point: To calculate the reorder point effectively, several factors must be taken into account. These factors are instrumental in ensuring that you order just the right amount of inventory to maintain a balance between stockouts and overstock.
[Reorder Point] = [Average Units Sold per day] x ([Lead Time] + [Safety Stock Days] )

Fixed Order Quantity: We allow to set the order quantity when run the report, or set the order quantity per different levels such vendor/ product / variant in the setting file. When the inventory on hand falls below the [Reorder Quantity], the reorder quantity will be set as the [Fixed Order Quantity].
[Reorder Quantity] = WHEN [Inventory on hand] + [Incoming Inventory] <= [Reorder Point] THEN [Fixed Order Quantity] ELSE 0

Automated Replenishment Scheduling

Assisty takes your inventory management one step further by offering an automated replenishment scheduling feature. Users can schedule reports to receive a list of products that have fallen below the Minimum Inventory Quantity. The scheduling options include daily or weekly reports, allowing you to stay on top of your inventory needs without manual intervention.

Seamless Vendor Communication

In addition to scheduling reports, Assisty allows you to streamline communication with your vendors. You can add your vendor's email addresses to the recipient list of the scheduled reports. This means that your vendors receive automatic notifications of which products need replenishment. They can then initiate purchase orders for these products without the need for extensive communication on your end. It fosters efficient and proactive vendor relationships, ensuring a smoother supply chain.


In the world of inventory management, simplicity and consistency are keys to success. The Fixed Quantity Order Model offers just that. It simplifies replenishment, optimizes order quantities, and ensures product availability without the hassle of overstock or stockouts.

Mastering this model empowers your business with efficient inventory control. It's your ticket to streamlined management, reduced costs, and consistent customer satisfaction. Start now and watch your business thrive.

Updated on: 22/11/2023

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