Sell-Through & Weeks-of-Supply Calculator
Calculate sell-through, stock coverage, inventory variance, and target-unit gap.
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Compare gross margin with the inventory investment required to earn it.
Calculate gross margin return on inventory investment, inventory turnover, annualized turnover, margin rate, and inventory days from sales, cost of goods, and average inventory.
Calculator
Keep sales, cost of goods, and inventory on the same cost basis and period.
Use a complete period and inventory values at cost. The annualized views make periods easier to compare, but they can overstate a short or highly seasonal trading window.
Reading the result
Read margin productivity alongside the speed of inventory movement.
GMROI estimates how many units of gross-margin value were generated for each currency unit tied up in average inventory. Turnover shows how often average inventory moved through cost of goods during the period. Read both with margin rate, stock age, and category role.
Before you act
A ratio cannot explain why an item moved or stalled.
The result does not account for stockouts, lost sales, returns, vendor funding, markdown timing, transfer activity, seasonality, or differences between accounting and merchandising inventory records.
FAQ
Questions this tool helps frame.
Is GMROI the same as gross margin percentage?
No. Gross margin percentage compares margin with sales. GMROI compares gross margin dollars with average inventory held at cost.
Why should inventory be entered at cost?
Cost basis keeps the inventory investment consistent with cost of goods sold and the standard GMROI and turnover formulas.
What does annualized turnover mean?
It scales the entered period to a twelve-month rate for comparison. Treat it cautiously when the period is short or seasonal.
Can a high turnover still be a problem?
Yes. It can reflect efficient movement, but it can also accompany stockouts, missed demand, or margins that are too thin.
Working notes
Keep the formula with the assumptions.
- GMROI = Gross Margin Dollars / Average Inventory at Cost; Turnover = Cost of Goods Sold / Average Inventory at CostGross margin dollars are net sales minus cost of goods sold. Average inventory uses the beginning and ending inventory values entered at cost.
- Update the result when the record changesSupplier terms, sales, stock, costs, timing, and channel deductions can change the result materially.
- Continue the operating reviewScaffold, MomentumFinancial, TCKRprice
- Check the connected numbersSell-Through & Weeks-of-Supply Calculator, Inventory Carrying Cost Calculator, Open-to-Buy Calculator.
- Prepare the non-financial questionsSupplier Readiness Assessment, Funding Readiness Assessment.
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