2026 Amazon Reorder Point & Days-of-Supply Calculator: Calculate exact replenishment reorder triggers, safety stock buffers, days of supply, and stockout dates.
Inventory & Lead Time Inputs
days
Production + Transit + FC Check-indays
Recommended: 14–30 daysInventory Status Output Below ROP — Order Now!
Target Reorder Point (ROP)
1,100 units
Trigger reorder when inventory drops to 1,100 units
Days of Supply24.0 daysStockout: Oct 17, 2026
Days Until Reorder0 daysTrigger: Sep 3, 2026
Low-Inventory-Level Fee Risk: Below 28 days of supply triggers Amazon's low-inventory-level fee on all shipped customer orders. Replenish immediately to clear the 28-day threshold!
Reorder Formula Accounting
Mathematical BreakdownLead Time Demand (30 days × 25.0/day):750 units
+ Safety Stock Buffer (14 days × 25.0/day):+350 units
= Total Target Reorder Point (ROP):1,100 units
Frequently Asked Questions — Amazon Reorder Point & Days of Supply
Learn how to prevent Amazon stockouts and avoid low-inventory surcharge fees
What is an Inventory Reorder Point (ROP)?▼
Reorder Point (ROP) is the exact inventory level that triggers a new inventory replenishment order. It equals (Average Daily Sales × Lead Time in Days) + Safety Stock Units.
Why does Amazon penalize inventory below 28 days of supply?▼
Under Amazon's 2026 fee policy, if a SKU's historical days of supply (both 30-day and 90-day averages) falls below 28 days, Amazon assesses a Low-Inventory-Level Fee on every unit shipped to buyers.
How do lead times affect inventory reorder triggers?▼
Lead time encompasses total supplier manufacturing time, ocean/air transit duration, customs clearance, and Amazon FC check-in processing. Longer lead times require higher reorder points to avoid stockouts.
What is safety stock and how many days should I keep?▼
Safety stock is buffer inventory kept to protect against unexpected supplier delays or sales spikes. Standard recommendation for Amazon sellers is 14 to 30 days of safety stock.
How is the projected stockout date calculated?▼
Stockout date = Today's Date + Days of Supply. Days of Supply equals Current Inventory divided by Average Daily Sales.
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