Free · Financial ratios
Inventory Turnover & Days Calculator
Compare cost of goods sold with average inventory and estimate inventory days.
- Formula & worked example
- Private in your browser
- No signup
Your calculation
Enter enough known values to calculate the blanks.
Use one currency for your figures. Mixed-currency conversions use rates captured October 5, 2026, rather than live exchange rates.
How to use this calculator
- Enter the values you know in the units shown. Leave unknown values blank.
- Results update automatically as you type. Edit a result to calculate another value, or lock a value to keep it fixed.
- Reset restores the starting fields. A worked example appears below.
Use the result with context
Results are estimates for planning and education. Confirm rates, taxes, fees, and legal requirements with the relevant institution or a qualified professional before making a financial decision.
Formula and method
Inventory turnover is cost of goods sold divided by average inventory. Inventory days expresses that rate as a duration using the calculator's annual-day assumption.
Cost of goods sold ÷ Average inventory
Worked example
Enter these known values and leave the other values blank.
- Cost of Goods Sold
- 120000 USD
- Beginning inventory
- 15000 USD
- Ending inventory
- 25000 USD
- Period
- 365 days
- Inventory days
- 61
- Inventory turnover
- 6
- Average inventory
- 20000 USD
Assumptions and limitations
- Inputs must satisfy the validation rules. Editing a result can recalculate an earlier input; lock values you want to keep fixed.
- Currency conversions use the captured source rates from October 5, 2026; they are not live exchange rates.
Common questions
What does this inventory turnover calculation tell me?
Inventory turnover is cost of goods sold divided by average inventory. Inventory days expresses that rate as a duration using the calculator's annual-day assumption.
Can I calculate a different unknown?
Yes. Clear that field and enter the other known values. The calculator uses the available inverse equations.
References
The calculation equations, inverse formulas, units, and input rules were imported from this source. Bookify provides the interface and equation solver.