Stock Keeping Unit (SKU)

A retailer- or brand-assigned code identifying a specific product variant, such as size or colour, for inventory and sales tracking.

By Brandon MinaCEO, BrandPilot AIUpdated November 2026

Short answer

A stock keeping unit (SKU) is a code a retailer or brand assigns to identify a specific product variant, such as a particular size, colour, or pack. Each variant gets its own SKU. SKUs are used to track inventory, sales, and reorders precisely, and they form the basic unit for reporting in retail media.