Nettobedarf

Nettobedarf, or net requirement, is a term used in production planning and materials management to denote the quantity of a material that must be procured or produced in a planning horizon to satisfy demand after accounting for existing inventory and planned receipts. It represents the actual amount needed beyond what is already available.

The calculation of Nettobedarf typically starts from the gross requirements (Bruttobedarf), which are the total demands for a component or material derived from the production schedule and demand forecasts. From this, the available stock and expected receipts are subtracted. Available stock includes the on-hand inventory and any scheduled or in-transit receipts. If the result is negative, the net requirement is zero. In practice, safety stock and lead times can influence the net requirement, as safety stock acts as a buffer and may lead to ordering more even when a positive net requirement exists.

Nettobedarf is distinct from Bruttobedarf in that it reflects what remains to be supplied after accounting for what is already or will be available. It also interacts with available-to-promise calculations and inventory planning, guiding procurement, production orders, and scheduling within an integrated planning system.

In application, Nettobedarf is a central concept in material requirements planning (MRP) and ERP systems. It drives purchase requisitions and manufacturing orders, helping organizations determine when to procure or produce materials and how to maintain desired inventory levels throughout the planning horizon.