Eräkoon

Eräkoon is a Finnish term used primarily in manufacturing, logistics and procurement to refer to the size of a batch or lot. The word is formed from erä (batch, lot) and the genitive form of koko (size), koon, yielding eräkoon, literally meaning the batch size.

Usage is common in planning documents, production scheduling, and ERP-system terminology. It denotes how many units are produced, ordered, or stored together as a single batch and thus influences cost and lead times.

Determining eräkoon involves balancing fixed costs associated with setup or order processing against variable costs of holding inventory. In practice, methods similar to batch sizing and the economic order quantity are used, but the term itself is not a strictly standardized technical term in Finnish; you may also encounter erän koko or erän määrä depending on context.

Because of its limited standardization, the term is largely contextual and may be defined differently across companies. It is mainly relevant for operations planning, inventory control, and procurement strategies.

See also: Lot size, Batch size, Inventory management, Economic order quantity.