Sell-Through Rate Calculator
See how fast your inventory actually moves — with sell-through rate, inventory turnover, days in stock (DIO), and the real carrying cost of capital sitting on the shelf.
All math runs locally in your browser. Nothing is uploaded.
How to read these numbers
| Metric | Formula | What it tells you |
|---|---|---|
| Sell-through rate | Units sold ÷ units received × 100 | % of the batch that sold in the window |
| Sales velocity | Units sold ÷ days | Average units moving per day |
| Inventory turnover | (COGS sold ÷ avg inventory) annualised | How many times stock cycles per year |
| DIO | 365 ÷ turnover | Average days an item sits unsold |
| Carrying cost | Remaining value × carrying % | Capital, storage & obsolescence tied up |
Carrying cost typically runs 20-30% of inventory value per year across warehousing, insurance, shrinkage, and the opportunity cost of money.
Frequently asked questions
What's a good sell-through rate?
For a full season, 60-80% is generally healthy; fast-fashion and trend items should move quicker. A very low rate signals over-ordering, weak demand, or a pricing problem. Compare within your own category over time rather than against a single universal number.
Sell-through vs inventory turnover — which should I track?
Both. Sell-through is best for judging a specific buy or collection in its window. Turnover and DIO are annual, value-based measures that show overall capital efficiency and are easier to compare across the whole business.
Why is low turnover dangerous even if sales are fine?
Slow turnover means cash is locked in stock for longer, storage and obsolescence costs rise, and trend-driven goods may have to be marked down. Two stores with the same sales total can have very different cash health depending on turnover.