Amazon Reorder Point Calculator — Safety Stock & Stockout Warning
Enter your sales velocity, replenishment lead time and on-hand stock to get your reorder point, safety stock and days of cover — with an early warning when a regular replenishment can no longer outrun a stockout. Everything runs in your browser.
Fill in the required fields — results update as you type.
Avg daily sales = window sales ÷ window days. Safety stock = (max daily − avg daily) × lead time — it buffers demand spikes during the wait. Reorder point = avg daily × lead time + safety stock: when on-hand stock drops to this number, place the order. Days of cover = on-hand ÷ avg daily; once that's below the lead time, a normal-speed replenishment can't save you.
All calculation happens in your browser with local JavaScript — nothing you type is uploaded.
Already stocked out and lost rank? Read the negative-review triage playbook →