Inventory glossary
What is Unit of measure?
Unit of measure is the quantity label used to count, order, and sell a product, such as each, case, box, or dozen.
Unit of measure matters because suppliers and stores do not always count the same way. A supplier may sell in cases of 12 while you sell to customers one at a time. If you mix these up on a purchase order or in your stock count, you can order ten times too much or too little without noticing.
Set one clear unit of measure for selling and one for ordering, and know the conversion between them. Write both on your product records and purchase orders so nobody has to guess whether "10" means 10 units or 10 cases.
Example
A candle shop sells candles individually on their store, so the selling unit of measure is "each". Their wax supplier only ships in cases of 6. If the shop needs 90 candles, they must order 15 cases, since 90 / 6 = 15. If someone mistakenly orders 90 cases, that is 540 candles, far more than needed.
Common mistakes
- Confusing the selling unit with the supplier's ordering unit and placing an order the wrong size.
- Not recording the conversion rate between units, so staff guess and get it wrong later.
- Changing a supplier's case size without updating the unit of measure on file, causing future orders to be miscalculated.
Unit of measure and SteadyShelf
SteadyShelf uses each supplier's case pack as the ordering unit of measure so suggested order quantities round up to full cases automatically.
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Related terms
Case pack · Purchase order · Reorder quantity · SKU · Minimum order quantity
FAQ
Why does unit of measure matter for a small Shopify store?
It prevents ordering mistakes. If you sell by the unit but your supplier ships by the case, mixing those up on a purchase order can mean receiving far too much or far too little stock.
Can a product have more than one unit of measure?
Yes. A common setup is selling in "each" to customers while ordering in "case" from the supplier. You just need to know the conversion, such as 1 case equals 12 each, to keep orders accurate.
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