What this calculator does
A reorder point is the on-hand plus on-order position at which replenishment should be initiated. This version combines average demand expected during lead time with separately chosen safety stock.
When to use it
Use it for repeatable MRO consumption where demand history and supplier lead time can be expressed in a common unit. It is a control parameter, not the recommended order quantity.
Inputs and formula
Average demand is units per day; lead time is days; safety stock is units. Reorder point = average daily demand × lead time + safety stock
Worked example and interpretation
3 units/day for 21 days requires 63 units through replenishment. Adding 18 units safety stock produces an 81-unit trigger. Review the result against minimum order, shelf life, storage, and item criticality.
Practical notes and limitations
Use inventory position rather than only shelf quantity. Supplier lead time can vary, and repairable rotables may have a return loop rather than straightforward demand. Rare critical spares may need a policy-based stocking decision beyond this demand model.