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Amazon Inventory Reorder Calculator

Calculate your exact reorder point, safety stock, days until stockout, and optimal order quantity — never lose the Buy Box to an empty shelf again.

Used by FBA sellers managing 10–500+ active SKUs to prevent costly stockouts.

Sales & Stock

Find daily sales in Seller Central → Business Reports

Average units sold per day

units/day

Units available at FBA

units

Lead Time & Buffer

Time from order placement to units available for sale

Days from order to your door

days

Days to check-in and activate

days

Extra buffer days to hold

days

Supplier MOQ (leave 0 if none)

units

Optional

For capital requirements estimate

Your cost per unit from supplier

$/unit
Inventory Status
Stockout Risk!
Reorder Point
1,020 units
Order when stock hits this
Stock Coverage
25 days
At current velocity
Stock Coverage vs 90-day Target25 days
0 days90 days
Reorder By
4 Apr 2026
In 0 days
Stockout Date
29 Apr 2026
In 25 days
Order Details
Safety Stock Required280 units
Recommended Order Qty1,800 units
Recommendations
  • →CRITICAL: At current sales velocity you will stockout before new stock arrives. Expedite shipping immediately.
  • →Only 25 days of stock remaining. With 37-day lead time, act now.

Want automated inventory alerts?

We build Sellerboard inventory dashboards with real-time Slack alerts for FBA sellers.

Set Up Inventory Monitoring →

Amazon FBA Inventory Management Guide

What is the Amazon FBA reorder point?

Reorder Point = (Daily Sales × Total Lead Time) + Safety Stock. Total lead time = supplier lead time + FBA processing time (usually 5–14 days). When your FBA stock drops to this number, place your purchase order immediately to avoid stockouts.

Why does stockout destroy Amazon rankings?

When your listing goes out of stock, Amazon removes it from search results. You lose the Buy Box, organic rank drops significantly (often taking weeks to recover), and sponsored ads stop running. A single 2-week stockout can cost 30–60 days of lost rank momentum.

How much safety stock should I keep?

Most FBA sellers target 14–30 days of safety stock. The right amount depends on your supplier reliability and demand volatility. If your supplier is overseas (30+ day lead time) or you have seasonal peaks, increase to 30–45 days safety stock to buffer against delays.

Built by MishraBrandTechAi — we build automated FBA inventory monitoring systems with 7d/30d coverage tracking, reorder alerts, and Sellerboard dashboards for growing Amazon brands. See our inventory analytics work →