Buy by the carton, sell by the piece, count in either
Each item keeps its stock in one base unit and has its own conversions to every other unit it is traded in. A line in cartons lands in stock as pieces, and the numbers always agree.
- Base unit
- Piece
- Conversion
- 1 carton = 24 pieces
- Received
- 10 cartons
- In stock
- 240 pieces
Goes through · Sell 30 pieces and 210 remain, valued in the same base unit
How units are set up
Define the units
Keep one list of units for the company: piece, carton, kilo, and so on.
Give the item a base unit
Stock is held and valued in it. The item also names the unit it is usually traded in.
Add conversions
State how many base units each other unit holds, for that item alone.
Trade in any of them
Orders, receipts, transfers and counts take any unit the item converts.
Details that matter
Whole-number ratios
A conversion is stored as a pair, such as 24 to 1, not as a long decimal, so rounding never creeps in.
No rule, no line
A line in a unit the item has no conversion for is refused, naming the item and the unit.
Base unit fixed once used
After stock moves or conversions exist, the item’s base unit can’t change.
Questions buyers ask
Can two items have different carton sizes?
Yes. Conversions belong to the item, so one carton can hold 12 and another 24.
Can a barcode belong to a carton?
Yes. Each barcode is tied to one of the item’s units.
Can we price per carton?
Yes. A price list holds a price per item and unit.