Amazon FBA Reorder Point Calculator
Never run out of stock. Know exactly when to place your next inventory order.
Supplier production + transit time
Extra buffer — 7–14 days typical
Enter your current stock to see stockout risk
What Is a Reorder Point?
The reorder point (ROP) is the inventory level at which you should place a new order to replenish stock before you run out. Running out of stock on Amazon means losing the Buy Box, forfeiting sales rank, and handing customers to competitors — recovering from a stockout can take weeks.
The formula is: ROP = (Daily Sales × Lead Time) + Safety Stock
Lead time covers the total time from placing an order with your supplier to inventory becoming available at FBA — including production, transit, customs clearance, and check-in at the fulfillment center.
How Much Safety Stock Do You Need?
Safety stock is a buffer against variability — late shipments, customs delays, unexpected sales spikes. A common starting point is 1–2 weeks (7–14 days) of sales as safety stock. If your supplier is highly reliable and your sales are stable, you can use 7 days. If your supply chain has more variability (overseas manufacturing, ocean freight), 14–21 days is safer.
During Q4 (October–December), consider doubling your safety stock because both demand spikes and carrier delays are common.
Tips for FBA Inventory Management
- Use the last 30-day sales velocity from Seller Central rather than all-time averages — velocity changes seasonally
- Add 7–14 days to your supplier's quoted lead time to account for FBA check-in delays
- Set calendar reminders when inventory hits the ROP — don't rely on memory alone
- Use the weeks of cover calculator to visualize your runway
- Use the storage fee calculator to balance against overstocking costs
Frequently Asked Questions
What is a good reorder point for FBA sellers?
There's no universal number — it depends on your daily sales velocity and lead time. The formula (Daily Sales × Lead Time) + Safety Stock gives you the right number for your specific situation. A product selling 50 units/day with a 45-day lead time needs a reorder point of at least 2,250 units plus safety stock.
What should I include in lead time?
Lead time = supplier production time + transit time (ocean freight is typically 25–35 days from China) + customs clearance (3–7 days) + FBA receiving time (3–7 days). Total lead times from overseas suppliers often run 45–70 days.
What happens if I stock out on Amazon?
Stockouts cause you to lose the Buy Box, which means Amazon either shows competitors or shows your listing as unavailable. You also lose sales rank momentum — organic ranking drops can take weeks or months to recover. Avoiding stockouts is one of the highest-ROI activities for FBA sellers.
How often should I update my reorder calculations?
Review your reorder point at least monthly, or whenever sales velocity changes significantly (new ad campaign, seasonal shift, viral moment). A static ROP becomes inaccurate as your business grows or sales patterns shift.
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