Fill Rate
Share of customer demand met immediately from stock.
Formula
Variables
Example
940 of 1000 shipped: FR = 94%
How it works
Fill rate shows what percentage of customer orders were satisfied right away from available inventory. It works by comparing the number of units actually shipped to the number of units customers asked for, then converting that fraction into a percentage. A higher fill rate means fewer shortages, backorders, and delayed deliveries.
When to use it
Use this when you want to measure how well a warehouse, retailer, or distribution system is meeting demand from stock on hand. It is especially useful for tracking service levels, inventory performance, and the impact of stockouts.
Worked example, step by step
A store receives an order for 500 units of a product. It ships 470 units immediately from stock. FR = (units shipped / units ordered) × 100 FR = (470 / 500) × 100 FR = 0.94 × 100 FR = 94% So, the fill rate is 94%.
Common mistakes to avoid
- Using total inventory levels instead of the number actually shipped
- Forgetting to multiply the fraction by 100 to get a percentage
- Mixing up units ordered with units delivered late or backordered
Did You Know?
A 95% fill rate still means one in twenty order lines disappoints a customer.
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