Inventory Turnover Calculator
See how many times your stock turns over in a year — and how many days of supply that leaves on the shelf. Work it in dollars from COGS and average inventory, or in units from what you sold and what you hold.
Inventory turnover
What turnover tells you
Inventory turnover is how many times you sell through and replace your average stock in a year. Turn faster and less cash sits on the shelf, and your carrying cost drops with it. Turn too slowly and you’re paying to store money in the form of product.
Turnover = COGS ÷ average inventory · Days of supply = 365 ÷ turnover
Cost or units
In dollars, divide the year’s cost of goods sold by the average inventory value. In units, divide units sold by average units on hand. Both give the same turns; units are handy for a single SKU, dollars for the whole operation.
Days of supply
Flip turnover into time and you get days of supply — 365 divided by the turns. Six turns a year is about 61 days on hand. It’s the everyday way to say how long today’s inventory would last.
More turns means less average inventory — and directly less carrying cost. The two tools read best side by side.