SKU

A stock-keeping unit — the distinct item identity you buy, store, count, and sell as one row in inventory (often size, colour, or pack specific).

Also searched as: stock keeping unit, item code, product variant, inventory item number

SKU is an operations identity, not a marketing name. “Blue tee” may be one product on the website and six SKUs in the warehouse (S/M/L × slim/regular). Each SKU has its own quantity, cost, and barcode.

Too few SKUs and you cannot tell which variant is out of stock. Too many and purchasing, counting, and costing drown in variants nobody sells. Good catalogues collapse vanity variants and split anything that moves differently.

If you sell one undifferentiated service, you may never need SKUs. The moment stock, serials, or packs matter, invent SKUs before you invent reports.

One style, two SKUs, two stock cards

Style BLUE-TEE sells in M and L. Opening: M = 12 units at $8, L = 5 units at $8. Sell 3 × M.

  1. SKU BLUE-TEE-M on hand after sale = 12 − 3 = 9; COGS = 3 × $8 = $24.
  2. SKU BLUE-TEE-L unchanged = 5 units.
  3. Style-level “blue tee” sales = 3, but replenishment must target BLUE-TEE-M, not L.

Treating both sizes as one SKU would hide that M is the one selling out while L sits.

Related modules

Related terms

FAQ

Is SKU the same as barcode?

Often one barcode maps to one SKU, but a SKU can have multiple barcodes over time. The SKU is the inventory record; the barcode is a scan alias.