Sell-through rate
Sell-through rate is the percentage of available inventory sold during a period. It is calculated as units sold divided by units available for sale (beginning stock plus receipts), multiplied by 100. Ecommerce operators use it to judge how well a buy matched demand and to time markdowns and reorders.
| Units sold | Units sold in the window, counted in units, not dollars |
| Units available for sale | Beginning inventory plus units received during the window |
Conventions differ: buying teams often compute sell-through against units received alone when judging a new drop with no opening stock. Both are valid - state which denominator you are using.
Worked example
A store receives 1,200 units of a new hoodie with no opening stock and prices it at $90 (example numbers).
Whether 65% in eight weeks is good news depends entirely on the plan. If the buy was meant to clear in six weeks, 420 units are heading for markdown. If it was a sixteen-week program, the line is ahead of plan.
What is a good sell-through rate?
There is no universal number, because sell-through only means anything against the sell-down plan you set when you bought the stock. What it depends on: the product lifecycle (a seasonal drop must clear before the season ends, an evergreen replenishment line just needs to outrun its reorder cycle), your markdown calendar, your replenishment lead time, and your margin structure - how much markdown the margin can absorb before the line goes underwater. Judge sell-through against the window and exit plan for that specific buy, not against a quoted industry figure.
Sell-through rate vs related metrics
| Metric | What it measures | How it differs |
|---|---|---|
| Inventory turnover | How many times average inventory converts to sales, at cost | A cost-based ratio, usually annualised for the whole business. Sell-through is a unit percentage over a specific window, usually for a specific buy. |
| Days of cover | How long current stock lasts at the current sales rate | Forward-looking runway in days. Sell-through looks backwards at how much of the buy has gone. |
| Stockout | Demand arriving with no stock to serve it | The endpoint of selling through too fast - the buy was too shallow. |
| Dead stock | Inventory that has stopped selling | The endpoint of selling through too slow - the buy outlived demand. |
Common mistakes
- Computing it on dollars. Markdowns and price changes distort a dollar-based rate mid-season. Count units.
- Quoting the rate without the window. 65% in two weeks and 65% in eight weeks are different businesses. Always state the period.
- Comparing SKUs with different receipt dates. A line that landed last week will always look worse than one that landed last month. Compare at the same age.
- Reading a high rate as a pure win. Selling out far ahead of plan usually means the buy was too shallow, and the unserved demand became a stockout, not revenue.
- Blending sizes and variants. A 65% line can be 95% sold in core sizes and dead in the tails. Sell-through is a per-variant number.
Frequently asked questions
In Blufire, S7 Inventory classifies every SKU on an ABC x XYZ grid and tracks days-of-cover and reorder timing, so slow sell-through surfaces as a margin problem before it becomes dead stock.
Updated July 2026