Free Online Inventory Reorder Point Calculator
Calculate when to reorder stock based on demand and lead time.
The reorder point is the stock level that triggers a new purchase order. It must cover demand during lead time plus safety stock.
About the Inventory Reorder Point Calculator
A reorder point is the inventory level at which a new purchase order should be placed. If you wait until stock reaches zero, the next order arrives after a gap and customers see a stockout. The reorder point accounts for how much stock is sold while the supplier is delivering, plus a safety buffer for demand spikes and late shipments. This calculator computes that threshold from average daily demand, lead time, and safety stock.
The basic formula is daily demand multiplied by lead time in days, plus safety stock. If a product sells eighteen units per day and the supplier takes twelve days, the lead-time demand is 216 units. With sixty units of safety stock, the reorder point is 276. When on-hand inventory falls to that level, the next order should already be on its way. The tool can also compare your current stock with the reorder point and recommend an order quantity. When current stock is at or below the threshold, it recommends at least the configured order quantity, and more if the shortfall is larger.
Safety stock is a judgment call. It protects against forecast error, seasonal demand, supplier delays, and quality holds. A common starting point is a few days or weeks of demand, but the right value depends on how variable your sales and lead times are. Higher safety stock reduces stockout risk and increases carrying cost. The lead time should be the realistic replenishment time, not the supplier's best-case promise. Include order processing, transit, receiving, and quality checks.
The recommended order is a simple rule, not an economic order quantity model. It does not balance ordering costs against holding costs, and it does not account for minimum order quantities, case packs, or container capacity. Adjust the result to your supplier's constraints. The unit cost and currency fields are only used to estimate the cash needed for the order. All calculations run locally.
Demand and lead time are averages, and averages hide risk. A supplier that is usually on time can still miss a delivery during a holiday or a port disruption. A demand spike from a promotion can empty a shelf in days. Service level targets, lead-time variability, and stockout cost should influence safety stock more than habit does. Review the reorder point when suppliers, shipping lanes, or sales patterns change, and keep a buffer for items with long or unreliable replenishment.
How to use this tool
- Enter average daily demand, lead time, and safety stock.
- Add your normal order quantity and, optionally, current stock.
- Review the reorder point, days of stock, recommended order, and stock status.
- Copy the summary into a purchasing plan or inventory review.
Frequently asked questions
What happens if I leave current stock blank?
The tool still calculates the reorder point and recommends your configured order quantity, but it cannot tell you whether to order today.
Should safety stock be included in the reorder point?
Yes. The reorder point covers expected demand during lead time plus the buffer you want to keep in reserve.
Does this calculate economic order quantity?
No. It uses the order quantity you provide. EOQ requires ordering cost and holding cost inputs, which are outside this calculator.