DIO Calculator Days inventory outstanding. Avg inventory ($) COGS ($) Days inventory (days) 73 Step-by-step with your numbers: 1. Values used: 2. Avg inventory = 100,000 $ 3. COGS = 500,000 $ 4. Days inventory = 73days Did we solve your problem today? 👍 Yes 👎 No Thanks for the feedback! How long inventory sits before selling. FAQ Lower is better? Generally yes. Related calculators DSO Calculator Days sales outstanding. DPO Calculator Days payable outstanding. Cash Conversion Cycle Calculator CCC = DIO + DSO − DPO.