Reorder Point Calculator

Calculate when to reorder inventory based on lead time and demand.

Average Daily Demand

units

Lead Time

days

Safety Stock (override)

units

Demand Std Deviation

units/day

Service Level (%)

Tab to move between fields

Reorder Point

1,523 units

Lead Time Demand1,400 units

Safety Stock123 units

Days of Coverage at ROP15.2 days

Annual Demand36,500 units

Z-Score1.65

How to Use This Calculator

Enter the average daily demand in units.
Set the supplier lead time in days.
Input your desired safety stock level.
Review the Reorder Point (ROP) — the inventory level at which to place a new order.
Trigger purchase orders automatically when on-hand inventory reaches the ROP.

How the result changes with Lead Time

Average Daily Demand: Average number of units sold or consumed per day.
Lead Time: Average number of days from order to delivery.
Safety Stock (override): Manual safety stock override (0 = auto-calculate).
Demand Std Deviation: Standard deviation of daily demand for safety stock calc.
Service Level (%): Desired service level (90, 95, 97, or 99%).

Identify Input Parameters
4 parameters
Average Daily Demand = 100, Lead Time = 14, Safety Stock (override) = 0, Demand Std Deviation = 20 = 5 input(s) provided
Calculate Reorder Point
Reorder Point
1523 = 1523
Calculate Lead Time Demand
Lead Time Demand
1400 = 1400
Calculate Safety Stock
123 = 123