Inventory reorder calculator.
Never stock out (lost rank) or overstock (storage fees). Find your reorder point and when to order.
Get a free audit ↗Reorder point = daily sales x (lead time + safety days). Order when inventory hits it. Suggested quantity covers your chosen days plus lead time.
Order before you run out, not after.
Your reorder point is the inventory level at which you must place a new order so it arrives before you sell out, allowing for supplier lead time plus a safety buffer for demand spikes and delays.
Stockouts cost rank
On Amazon, running out does not just lose sales; it drops your organic rank, which is expensive to win back. The safety buffer is cheap insurance.
Overstock costs fees
Ordering too much ties up cash and racks up storage fees, especially in Q4. Order to a target days-of-cover, not a round number.
How do I calculate a reorder point?
Multiply your average daily sales by the sum of supplier lead time and your safety-stock days. When inventory hits that number, place the order.
How much safety stock should I hold?
Enough to cover demand spikes and lead-time variability, often one to three weeks. More for unreliable suppliers or seasonal products.
Why does stocking out hurt on Amazon?
Running out loses sales and drops your organic rank and Buy Box, and recovering that position usually costs an ad spend push.
Estimates for planning only. Verify current Amazon fees in Seller Central; results depend on your inputs.
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