GMROI & Inventory Turnover Calculator
Calculate GMROI, turnover, gross margin, and inventory days for one review period.
Open toolOne Study decision-preparation calculator
Measure how quickly inventory is selling and how long the balance may last.
Calculate sell-through, weeks of supply, inventory reconciliation, and units above or below a target stock position from receipts, sales, and on-hand units.
Calculator
Review the same SKU, location, and time period throughout.
This view is most useful when sales, receipts, returns, and current stock are current. If inventory systems disagree, use the reconciliation difference to find the record that needs attention before acting on the result.
Reading the result
Use sell-through and coverage together, not in isolation.
Sell-through describes how much of the available inventory moved during the review period. Weeks of supply describes how long current stock would last at the entered weekly pace. The target-unit gap makes the comparison explicit without automatically choosing a reorder or markdown.
Before you act
Seasonality and future demand are not contained in the ratio.
The result does not forecast promotions, seasonality, returns, cancellations, stock transfers, lost sales, new distribution, lead-time changes, or demand shifts. Review those facts before changing an order or markdown plan.
FAQ
Questions this tool helps frame.
Why are sell-through and weeks of supply different?
Sell-through looks backward at how much available stock sold. Weeks of supply uses current stock and a sales pace to estimate coverage from today.
Should receipts be included in sell-through?
Yes, when they became available during the period. Keep the period and availability rules consistent across products you compare.
What does the reconciliation difference show?
It compares expected ending stock with the on-hand amount entered. A difference may reflect returns, transfers, shrinkage, timing, or a record error.
Does a low weeks-of-supply result always mean reorder?
No. Lead time, seasonality, planned exits, cash, inbound orders, and assortment strategy can all change the appropriate response.
Working notes
Keep the formula with the assumptions.
- Sell-Through = Units Sold / (Beginning Inventory + Receipts); Weeks of Supply = Current On Hand / Average Weekly Unit SalesUse one consistent review period for beginning inventory, receipts, and units sold. Current on-hand units and recent weekly sales establish the stock coverage estimate.
- Update the result when the record changesSupplier terms, sales, stock, costs, timing, and channel deductions can change the result materially.
- Continue the operating reviewScaffold, TCKRprice
- Check the connected numbersGMROI & Inventory Turnover Calculator, Reorder Point & Safety Stock Calculator, Markdown & Discount Impact Calculator, Open-to-Buy Calculator.
- Prepare the non-financial questionsSupplier Readiness Assessment.
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