Calculate the exact reorder point for your products. Enter daily sales, lead time, and safety stock to prevent stockouts and optimize orders.
The reorder point (ROP) is the inventory level at which you should place a new order with your supplier. It accounts for the time it takes to receive new stock (lead time) and includes a safety buffer for demand variability.
For e-commerce sellers, getting the reorder point right prevents two costly outcomes: stockouts that lose sales and damage rankings, and over-ordering that ties up cash and increases storage fees. The formula balances average demand during lead time with safety stock to absorb unexpected demand spikes.
This calculator computes your ROP from average daily sales, supplier lead time, and safety stock level. It also estimates the maximum inventory level you'll reach after receiving a new order, helping you plan warehouse capacity. Whether you are a beginner or experienced professional, this free online tool provides instant, reliable results without manual computation. By automating the calculation, you save time and reduce the risk of costly errors in your planning and decision-making process.
Manually monitoring stock levels is error-prone and time-consuming. A calculated reorder point creates a simple trigger: when stock hits this number, order more. This removes guesswork from purchasing decisions and systematically prevents stockouts. Having a precise figure at your fingertips empowers better planning and more confident decisions. Manual calculations are error-prone and time-consuming; this tool delivers verified results in seconds so you can focus on strategy.
Reorder Point = (Average Daily Sales × Lead Time in Days) + Safety Stock Demand During Lead Time = Average Daily Sales × Lead Time Maximum Inventory = Reorder Point + Order Quantity
Result: Reorder Point: 450 units
Average daily sales of 25 units times 14-day lead time = 350 units needed during lead time. Adding 100 units of safety stock gives a reorder point of 450 units. When inventory drops to 450, place a new order to avoid stockout.
The reorder point tells you WHEN to order; the economic order quantity (EOQ) tells you HOW MUCH to order. Together, they form a complete ordering policy. When stock reaches the ROP, place an order for the EOQ quantity. This minimizes total inventory costs while maintaining service levels.
Static reorder points assume constant demand and lead times. In reality, both fluctuate. Dynamic reorder points recalculate based on recent sales trends and actual supplier performance. Many modern inventory systems support dynamic ROP, updating automatically as data changes.
If you sell on multiple channels (Amazon, Shopify, wholesale), your reorder point must account for total demand across all channels. Monitor channel-specific velocity and allocate safety stock proportionally, or maintain separate ROP calculations per channel.
The reorder point is the inventory quantity at which you should trigger a new purchase order. It is calculated to ensure you have enough stock to cover demand during the time it takes for new inventory to arrive, plus a safety buffer.
Safety stock is the buffer inventory kept to protect against unexpected demand spikes or supply delays. The reorder point includes safety stock plus the expected demand during lead time. ROP = demand during lead time + safety stock.
No. Reorder points should be adjusted seasonally. Before peak periods, increase your daily sales estimate and potentially extend lead time assumptions. During slow periods, reduce the ROP to avoid overstocking.
Variable lead times increase the risk of stockout. Use the maximum realistic lead time rather than the average for your ROP calculation, or increase your safety stock to account for the variability. The safety stock calculator can help quantify this buffer.
Products with irregular or lumpy demand patterns (e.g., B2B orders) need larger safety stock buffers. Use standard deviation of demand in your safety stock calculation rather than simple averages, and set a higher service level target.
Yes. Most inventory management systems support automated ROP calculations and alerts. Feed in your sales data and lead times, set your desired service level, and the system will calculate ROP and trigger purchase orders automatically.