What is the difference between service level and fill rate?

What is the difference between service level and fill rate?

• A. Service level measures probability of meeting demand; fill rate measures the percentage of demand actually fulfilled from stock
• B. Service level is the percentage of orders filled on time; fill rate is probability of meeting demand
• C. Service level is the ratio of stockouts to demand; fill rate is the ratio of stock on hand to demand
• D. Service level measures probability of meeting demand; fill rate measures the percentage of demand actually fulfilled from stock

Answer: (D)

Difference between service level and fill rate in inventory management: Service level is the probability that demand will be satisfied from stock without experiencing a stockout during a replenishment cycle. It reflects the risk of running out and is used to set safety stock and reorder points to meet a target likelihood of fulfilling demand. Fill rate, on the other hand, is the fraction of total demand that is actually fulfilled from available stock, usually expressed as units delivered immediately divided by total units demanded. This means you can have a high service level (low stockout risk) while the fill rate isn’t 100% if some demand is backordered or fulfilled later; and you can have a high fill rate while still facing stockouts in some cycles that prevent meeting all demand. For example, if stockouts occur in 5% of cycles, the service level is 95%. If 92 of 100 demanded units are filled from stock immediately, the fill rate is 92%.

Difference between service level and fill rate in inventory management: Service level is the probability that demand will be satisfied from stock without experiencing a stockout during a replenishment cycle. It reflects the risk of running out and is used to set safety stock and reorder points to meet a target likelihood of fulfilling demand. Fill rate, on the other hand, is the fraction of total demand that is actually fulfilled from available stock, usually expressed as units delivered immediately divided by total units demanded. This means you can have a high service level (low stockout risk) while the fill rate isn’t 100% if some demand is backordered or fulfilled later; and you can have a high fill rate while still facing stockouts in some cycles that prevent meeting all demand. For example, if stockouts occur in 5% of cycles, the service level is 95%. If 92 of 100 demanded units are filled from stock immediately, the fill rate is 92%.