Days inventory outstanding calculator.
DIO is 365 divided by inventory turnover. Type your numbers; the calculator returns DIO, turnover, and the implied working capital sitting in stock.
How DIO is computed
Days inventory outstanding equals 365 divided by annualised inventory turnover, or equivalently average inventory divided by daily cost of goods sold. The two formulas return the same number when COGS is annualised correctly. The calculator below handles the annualisation for partial periods.
NYU-STERN 2026 INVESTOPEDIA 2026
Healthy DIO ranges
Grocery clears in 26 days at the median. Apparel sits closer to 90. Jewelry runs over 240. Use the industry selector inside the calculator to swap benchmarks.
Period choice
Lenders and auditors prefer trailing-twelve-month inputs. Monthly or quarterly inputs work for an internal flash, but annualise carefully: a 90-day window with seasonally heavy sales will flatter DIO if read raw.
How DIO ladders into the cash conversion cycle
Cash conversion cycle equals DIO plus days sales outstanding minus days payable outstanding. DIO is the inventory leg and usually the cheapest leg to move at the SMB scale.