Enter your cost of goods sold and beginning/ending inventory value below to calculate your inventory turnover ratio and days sales of inventory. See the inventory turnover guide and DSI glossary page for how to interpret the result.
Average inventory
$100,000
Inventory turnover ratio
6.00× per period
Days sales of inventory (DSI)
61 days
How to use this number
Track this ratio over time rather than as a one-off snapshot—a falling turnover ratio (rising DSI) across consecutive periods is often an early signal of overstocking or slowing demand, worth investigating before it shows up as a cash-flow problem.
Compare turnover by product category or SKU group where possible, not just at the whole-business level—a healthy overall ratio can still hide slow-moving categories quietly tying up cash.
No beginning inventory figure for the period? Work it out from COGS, purchases and ending inventory with the beginning inventory formula.
Frequently Asked Questions
What formula does this inventory turnover calculator use?
Inventory Turnover = Cost of Goods Sold (COGS) ÷ Average Inventory, where Average Inventory = (Beginning Inventory + Ending Inventory) ÷ 2. Days Sales of Inventory (DSI) is then 365 ÷ Turnover Ratio.
How do I know if the ratio this calculator shows me is good?
It varies significantly by industry—fast-moving goods like groceries often turn over 10-15+ times a year, while durable goods or make-to-stock manufacturing may reasonably turn over just a few times a year. Compare against your own historical trend and industry peers rather than one universal number.
Should I use annual or another period for COGS and inventory?
Annual figures are most common and give a turnover ratio in "times per year." You can use a shorter period (e.g., quarterly COGS and average inventory) for a more granular view, just be consistent between COGS and the inventory period you compare it against.
Does this calculator save my numbers?
No. This is a client-side calculation only—nothing is sent to a server or saved. Refreshing the page resets it to the defaults.
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