Fill rate refers to what metric?

• A. On-time delivery rate.
• B. Inventory turnover.
• C. Percentage of customer demand fulfilled from stock over a period; calculated as units delivered divided by units demanded.
• D. Total units produced divided by total units demanded.

Answer: (C)

Fill rate is a service level metric that measures how much of customer demand is fulfilled directly from available stock over a period. It is calculated as units delivered divided by units demanded, usually shown as a percentage. This focuses on stock availability and the ability to meet demand from on-hand inventory, rather than delivery timing or production output.

If some demand is backordered or not met from stock, the fill rate drops below 100%. This is different from on-time delivery, which worries about when deliveries arrive; from stock perspective, a shipment can be on time but still not fully meet demand if stock was insufficient. It’s also different from inventory turnover, which assesses how quickly inventory moves through the system, and from production-to-demand ratios, which relate to how much is produced relative to demand rather than how much is actually stocked and used to satisfy orders.

Example: if 200 units are demanded in a period and 180 are fulfilled from stock, the fill rate is 180/200 = 90%.