Inventory glossary
What is Pack size?
Pack size is the number of units in one purchasable unit from a supplier, such as a case of 12 or a box of 24.
Pack size controls how much you can actually order. If your supplier sells candles in cases of 6, you cannot order 10, you have to round to 12 or 6. Knowing pack size ahead of time stops you from building a purchase order with quantities the supplier will reject or silently round themselves.
Use pack size together with your reorder quantity to avoid waste. If you only need 8 units to cover demand but the pack size is 24, you may end up holding 16 extra units for months. Check whether a smaller pack size from a different supplier, or a lower minimum order quantity, would match your actual sales pace better.
Formula
Example
A candle shop needs 50 units of a scent to cover the next month. The supplier only sells in cases of 12. 50 / 12 = 4.17, so the store rounds up to 5 cases, which is 60 units. The store orders 60 instead of 50.
Common mistakes
- Ordering a quantity that is not a multiple of the pack size and having the supplier round it without telling you.
- Ignoring pack size when calculating reorder quantity, leading to orders that look right on paper but cannot be fulfilled as written.
- Assuming pack size is fixed when some suppliers offer different case sizes for the same product.
Pack size and SteadyShelf
SteadyShelf rounds suggested order quantities to each SKU's case pack size automatically when drafting a purchase order.
SteadyShelf is launching on the Shopify App Store. Join early access to get the install link first.
Related terms
Case pack · Minimum order quantity · Reorder quantity · Purchase order · Unit of measure
FAQ
Is pack size the same as case pack?
Yes, in most small store contexts pack size and case pack mean the same thing, the fixed quantity you must order in from a given supplier.
What happens if I order a quantity that does not match the pack size?
The supplier will usually round your order up or down to the nearest full pack, or send it back asking for a corrected quantity.
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