Inventory accuracy describes whether the stock recorded in the system matches the stock physically present, while on-shelf availability describes whether a listed product is physically present and accessible on the shelf when a shopper looks for it 1. The two metrics measure different points in the same chain.
What inventory accuracy covers
Inventory accuracy concerns the reliability of the stock record itself. System stock can diverge from physical stock through scanning errors, shrinkage, misplaced items and data delays, and when the inventory data is inaccurate, replenishment decisions become unreliable and shelf gaps grow 1. Inside Walmart's Retail Link, suppliers can see how many units they hold on-hand in-store, but this can produce phantom inventory, where the system reports stock that in practice never appears in a single store for weeks 2. RFID advocates argue that inventory accuracy begins with supplier sourced tagging, and that tagging standards across the supplier community support item level accuracy 3.
What on-shelf availability covers
On-shelf availability is a shelf-level execution measure 1. A product may sit in the warehouse, be marked "in stock" in the system, or wait in the store's backroom, and it still counts as unavailable from an OSA perspective if it is not on the shelf and visible to shoppers 1. Stock availability asks whether inventory exists within the system or store; on-shelf availability asks whether that inventory reached the selling shelf 1. OSA is calculated as the number of SKUs available on shelf divided by total listed SKUs, expressed as a percentage 1. Most global FMCG and retail studies point to a strong OSA rate of 95% to 98%, with performance below 95% starting to create measurable revenue loss 1.