Inventory Turnover Days Calculator
Reviewed by Hamza Gujjar, Algorithm Architect & Software Developer
Last updated: July 27, 2026
Disclaimer: This calculator is provided for informational and educational purposes only and does not constitute financial, medical, legal, or other professional advice. Always consult a qualified professional before making decisions based on these results.
How long inventory sits before it sells
DIO measures the average number of days inventory sits in stock before being sold - a lower DIO generally indicates more efficient inventory management, freeing up cash that would otherwise sit tied up on warehouse shelves.
Worked example
For $100,000 average inventory against $600,000 in annual cost of goods sold:
DIO = (100000 / 600000) x 365 = 60.83 days
Extremely low DIO isn't automatically better, though - cutting inventory too thin risks stockouts and lost sales, so the ideal DIO balances carrying cost efficiency against having enough stock on hand to meet customer demand reliably.