Inventory Calculator
Local ProcessingSafety stock, inventory turnover and days of stock remaining.
How It Works & Processing Standards
Enter values above to calculate results automatically. Check each input field for guidance and units.
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Three inventory calculations in one place. Choose safety stock, turnover or days of supply under "Calculation".
What You Can Do
- Safety stock
- (max daily usage × max lead time) − (average daily usage × average lead time)
- Inventory turnover
- COGS ÷ average inventory — how many times stock sold through in a year.
- Days of supply
- current stock ÷ average daily sales — how many days it will last.
How to Use Inventory Calculator
- 1Choose a calculationPick the metric you need.
- 2Enter numbersUse consistent units (items, money). Periods are in days.
- 3Read the resultSafety stock is a quantity, turnover a count, days of supply days.
Examples
Safety stock
Input: Max 60/day × 10 days, average 40/day × 7 days
Result: 320
Annual turnover
Input: COGS 120,000,000, average inventory 20,000,000
Result: 6 times
900 in stock, 30 sold per day
Input: Stock 900, average 30
Result: 30 days
Common Use Cases
- Setting a reorder point
- Finding items that sit in the warehouse too long
- How long stock lasts before a holiday or event
Frequently Asked Questions (FAQ)
Is a high turnover good?
Usually — stock sells quickly — but very high turnover raises the risk of running out. Compare with your industry.
How is average inventory calculated?
Commonly (opening stock + closing stock) ÷ 2.