About the Days Inventory Outstanding Calculator
Days inventory outstanding (DIO): how many days of sales your current stock covers.
Also known as: dio calculator, days of inventory, inventory days on hand.
How to use this calculator
- Enter average inventory, annual cogs.
- The result updates instantly as you type — press Calculate (or Enter) at any time.
- Review the breakdown shown under the main result.
- Use Copy result or Share to save the answer or send a link with your inputs.
Formula
DIO = average inventory ÷ COGS × 365
Worked example
Using the values pre-filled in the calculator above:
- Average inventory = 180,000
- Annual COGS = 1,200,000
the calculator returns:
- Days inventory outstanding: 54.8 days
- Inventory turns per year: 6.67 ×