Know when to reorder.
A free inventory reorder point calculator with stock coverage, safety stock, inventory position, and order quantity estimates.
Your inputs
01 / CalculateYour estimate
02 / ResultCompare position with the reorder point.
Reorder point = average daily demand × lead time + safety stock. Inventory position = on hand + on order − allocated. Reorder when position is at or below the reorder point.
The suggested quantity brings inventory position to demand × (lead time + extra coverage days) + safety stock. It rounds up to whole units.
A worked example
At 4 units per day, a 7-day lead time and 10 safety units give a reorder point of 38. With 25 on hand, 10 incoming and 5 allocated, position is 30. A further 7 days of coverage gives a target of 66, so the estimated order is 36 units.
Read: reorder points and safety stock →Planning assumptions
Does this predict demand or supplier delays?
No. You provide demand, lead time, and the safety buffer. This is a simple planning model, not a forecast or service-level guarantee. Recheck unusually variable or seasonal items.
What counts as on order or allocated?
Include incoming stock you expect to be usable within your planning horizon. Allocated means units reserved for customers that are still included in on-hand stock. Do not subtract an allocation a second time if your on-hand figure is already net of it.
What if there are no sales?
Days of stock cover is undefined at zero demand. Review inactive stock manually. Inventory value uses the unit cost you enter, not FIFO, weighted-average, tax or accounting valuation.
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