Reorder Point Calculator
Find the stock level that should trigger your next purchase order. ROP = (average daily sales × lead time) + safety stock — instant results, no sign-up.
Reorder Point Calculator
Enter your average daily sales, supplier lead time and safety stock. The reorder point is the stock level at which you should raise the next PO.
Use stockout-adjusted average sales (units sold ÷ days actually in stock) and delivered — not quoted — lead times.
The formula, and a worked example
The reorder point answers “when should I order?” It is the expected sales during the supplier’s lead time, plus the safety stock that absorbs surprises. Order when stock reaches that level and the delivery should arrive just as you eat into the buffer — not after the shelf is empty.
Worked example: a SKU sells 6 units/day, the supplier takes 18 days, and safety stock is 142 units. Lead-time demand = 6 × 18 = 108 units; reorder point = 108 + 142 = 250 units. When stock hits 250, the next purchase order goes out.
The two inputs people get wrong are the average (raw history counts stockout days as zero-demand days — divide by days in stock instead) and the lead time (use what suppliers actually deliver, not what they quote). The full detail is in the reorder point formula guide; size the buffer first with the safety stock calculator, and work out how much to order with the EOQ calculator.
One SKU is arithmetic; a whole catalogue is maintenance. Inventory replenishment software recalculates reorder points continuously from live sales and lead times, and raises the purchase order automatically when the trigger fires.
Reorder Points That Maintain Themselves
Replenagise recalculates reorder points per SKU from live Shopify and Linnworks data — and turns every trigger into a purchase order automatically.