About the Inventory Turnover Calculator
Inventory turnover tells how many times a business sells and replaces its stock in a year. This calculator takes the cost of goods sold and the stock at the start and end of the period, and gives the turnover, the average stock and the number of days it takes to sell it. Type cost of goods sold and opening and closing inventory and the inventory turnover appears at once, with a few related figures underneath, and you can copy the result with one tap. The sums run in your browser, so nothing you enter is uploaded.
Updated October 2026
How to use the Inventory Turnover Calculator
- 1Enter cost of goods sold and opening and closing inventory.
- 2Pick the units or options from the menus if the inventory turnover tool offers them.
- 3Read the inventory turnover in the large result box.
- 4Look at the extra rows for related figures.
- 5Press Copy result to keep the answer.
When you need the inventory turnover
Shop owners and buyers use it to avoid overstocking, and analysts compare it between firms.
A higher turnover usually means efficient buying and strong sales, while a low figure may point to slow stock or too much buying. Sectors differ: a grocer turns stock over faster than a car dealer.
How the inventory turnover is worked out
Inventory turnover = cost of goods sold ÷ average inventory, where average inventory = (opening + closing) ÷ 2. Days of stock = 365 ÷ turnover. Cost of goods sold of 600,000 with stock of 90,000 at the start and 110,000 at the end gives an average of 100,000, so turnover is 6 and stock sells in about 61 days.
Every answer on this page comes from that one rule, so you can check any result by hand with a calculator. The figures shown underneath, such as other units, are conversions of the same answer.
- Turnover and days
- Average inventory
- Simple inputs
Mistakes to avoid with inventory turnover
Use cost of goods sold and not sales in the top line, or the result is overstated. Seasonal firms may need a better average than just the start and the end.
On phone and computer
On a phone, type into the boxes one after another and read the inventory turnover underneath; Copy result puts it on the clipboard for a message or a note. On a computer the inputs sit on the left and the answer on the right, so you can change one figure and watch the inventory turnover move. The inventory turnover calculator works the same on both.
Checking your inventory turnover by hand
A good habit is to test the inventory turnover calculator with a case you already know. Cost of goods sold of 600,000 with stock of 90,000 at the start and 110,000 at the end gives an average of 100,000, so turnover is 6 and stock sells in about 61 days.
If your own figures give a surprising answer, repeat the working yourself: Inventory turnover = cost of goods sold ÷ average inventory, where average inventory = (opening + closing) ÷ 2. Days of stock = 365 ÷ turnover. Small differences usually come from rounding, from mixing units, or from a typing slip in one of the inputs. How fast stock sells matters most next to margin and cash. Work out what each sale leaves with the Contribution Margin Calculator, check short-term cover with the Current Ratio Calculator, and find the sales needed to cover costs with the Break-Even Calculator.
Features
- Use cost, not sales
- Seasonal stock needs more data
- Compare similar sectors
- Clear messages when the inventory turnover inputs make no sense
- Copy the result with one tap
- Private: nothing is uploaded
Frequently asked questions
How do I calculate inventory turnover?
Inventory turnover = cost of goods sold ÷ average inventory, where average inventory = (opening + closing) ÷ 2. Days of stock = 365 ÷ turnover. Cost of goods sold of 600,000 with stock of 90,000 at the start and 110,000 at the end gives an average of 100,000, so turnover is 6 and stock sells in about 61 days.
What is the formula for inventory turnover?
Inventory turnover = cost of goods sold ÷ average inventory, where average inventory = (opening + closing) ÷ 2. Days of stock = 365 ÷ turnover. The inventory turnover calculator applies it exactly and rounds only the displayed answer to six significant figures.
What is a good inventory turnover?
It depends on the sector; groceries are high and furniture is low.
Why use cost and not sales?
Stock is recorded at cost, so cost of goods sold matches it.
How do I get days of stock?
Divide 365 by the turnover.
Is this inventory turnover calculator free and private?
Yes. It is free, needs no account and runs in your browser, so the numbers you type are not uploaded or stored.