Reorder Point Calculator
Calculate the inventory level that triggers a new order so stock arrives before you run out.
How it works
- 1Enter your average daily demand — how many units you sell or consume per day.
- 2Enter your supplier lead time in days and your desired safety stock buffer.
- 3The calculator returns your reorder point: ROP = (demand × lead time) + safety stock.
Use cases
- Retail and e-commerce businesses setting automatic reorder triggers in their inventory system.
- Manufacturing plants ensuring raw materials arrive before production lines stall.
- Warehouse managers building a safety buffer against demand spikes or supplier delays.
Frequently asked questions
What is the reorder point formula?
ROP = (average daily demand × lead time in days) + safety stock. For example, 50 units/day × 7 days + 30 units of safety stock = 380 units. When on-hand inventory drops to 380 units, place a new order.
What happens if I set safety stock to zero?
With zero safety stock your ROP equals demand during lead time only. Any demand spike or supplier delay risks a stockout. A safety buffer is recommended for most products.
How does the reorder point relate to EOQ and safety stock?
ROP tells you when to order; Economic Order Quantity (EOQ) tells you how much to order; safety stock sets your buffer against variability. Use all three together for a complete inventory policy.
Related tools
See all →Find the gear ratio, output speed, torque, and mechanical advantage of a gear pair, in metric or imperial.
Calculate the overall ratio and output speed of a multi-stage compound gear train.
Calculate shaft torque from power and rotational speed in metric or imperial units.
Calculate the mechanical power transmitted by a rotating shaft from torque and shaft speed.