Inventory Accuracy Formula

What Inventory Accuracy measures

Inventory accuracy is the match between system-recorded inventory and physical inventory. Low accuracy makes every allocation decision based on bad data — shipping against stock that isn't there and holding stock the system doesn't see.

Worked apparel example

A DC system shows 5,000 units of a SKU; physical count shows 4,930.

Accuracy % = 1 − |5,000 − 4,930| ÷ 5,000 = 1 − 1.4% = 98.6%

98.6% accuracy is healthy. At 95% — common in brands without cycle-count discipline — allocation starts shipping against phantom inventory and triggering shorts.

Benchmark ranges

Why accuracy compounds

Every allocation decision, replenishment trigger, and reorder calculation depends on the system inventory read. A 95% accuracy rate means 5% of decisions are made on wrong data — but the impact compounds:

• →Short shipment → chargeback
• →Phantom stock shown to customer → cancellation
• →Over-stocked SKU not flagged → aged inventory
• →Safety-stock buffer consumed invisibly → stock-out

How RetailNorthstar handles inventory accuracy

The system reconciles continuously against the WMS feed, flags variances in real time, and attributes them (shrink vs miscount vs system drift). Cycle counts prioritize the SKUs where variances are emerging, not a fixed rotation.

Related formulas

• →Fill Rate — low accuracy drives fill-rate miss
• →Replenishment Trigger — trigger fires late if the system read is wrong
• →Safety Stock — safety stock compensates for accuracy loss, but inefficiently