Free FBA tools
Amazon FBA Calculators
Free, interactive calculators for the inventory math every Amazon FBA seller runs: when to reorder, how much buffer to hold, and how much to order. Each runs entirely on the numbers you type. No login, no ASIN, nothing stored, and free to embed on your own site.
FBA Restock Calculator
Get your Amazon reorder point, safety stock, and exactly how many units to send to FBA from your sales velocity and real lead times.
Open calculatorSafety Stock Calculator
Size the buffer that keeps you in stock through demand swings, using the statistical service-level formula.
Open calculatorEOQ Calculator
Find the order quantity that minimizes combined ordering and holding cost, with a live cost curve.
Open calculatorInventory Hero
Run this math automatically for every SKU
These calculators size one SKU at a moment in time. Inventory Hero tracks every SKU's real sales velocity, demand variability, and lead time, then keeps your reorder points, safety stock, and order quantities current as your sales and suppliers change.
14-day free trialNo credit card required.