Inventory Calculators

Inventory turnover, reorder point, safety stock, EOQ, days of inventory, holding cost and shrinkage.

Inventory
Inventory Turnover Calculator
Inventory turnover ratio and days inventory outstanding from COGS and average inventory.
Turnover = COGS ÷ average inventory
Also called stock turnover · inventory turns
Days Inventory Outstanding Average Inventory Cost of Goods Sold
Inventory
Average Inventory Calculator
Average inventory value over a period from beginning and ending inventory (or several period counts).
Average inventory = Beginning + ending in…
Also called mean inventory · average stock level
Inventory Turnover Inventory Value Reorder Point
Inventory
Reorder Point Calculator
Reorder point (ROP) from average daily usage, lead time and safety stock — when to place the next order.
ROP = daily usage × lead time + safety st…
Also called rop calculator · when to reorder
Safety Stock Economic Order Quantity Stock Coverage
Inventory
Safety Stock Calculator
Safety stock using the max-usage method or a service-level (z-score) formula with demand variability.
Max method: (max usage × max lead) − (avg…
Also called buffer stock · safety stock formula
Reorder Point Economic Order Quantity Days Inventory Outstanding
Inventory
Economic Order Quantity Calculator
EOQ — the order size that minimises total ordering and holding cost — with orders per year and total cost.
EOQ = √(2DS / H)
Also called economic order quantity · eoq formula
Reorder Point Inventory Holding Cost Days Inventory Outstanding
Inventory
Days Inventory Outstanding Calculator
Days inventory outstanding (DIO): how many days of sales your current stock covers.
DIO = average inventory ÷ COGS × 365
Also called dio calculator · days of inventory
Inventory Turnover Stock Coverage Inventory Holding Cost
Inventory
Stock Coverage Calculator
How many days, weeks or months your current stock will last at the current sales rate.
Coverage = stock ÷ daily sales
Also called days of supply · weeks of cover
Days Inventory Outstanding Reorder Point Inventory Holding Cost
Inventory
Inventory Holding Cost Calculator
Annual inventory carrying cost from storage, capital, insurance, shrinkage and obsolescence rates.
Holding cost = inventory value × carrying…
Also called carrying cost · inventory carrying cost
Economic Order Quantity Inventory Value Inventory Shrinkage
Inventory
Inventory Shrinkage Calculator
Shrinkage rate: inventory lost to theft, damage or error as a percentage of recorded stock or sales.
Shrinkage rate = Value of missing invento…
Also called shrink rate · inventory loss
Inventory Value Inventory Holding Cost Inventory Turnover
Inventory
Inventory Value Calculator
Total value of stock on hand at cost and at retail, with the implied retail margin.
Value = Σ quantity × unit cost
Also called stock value · inventory valuation
Inventory Turnover Inventory Holding Cost Average Inventory

Key inventory formulas

Inventory Turnover	Turnover = COGS ÷ average inventory
Average Inventory	Average inventory = Beginning + ending inventory ÷ Number of counts
Reorder Point	ROP = daily usage × lead time + safety stock
Safety Stock	Max method: (max usage × max lead) − (avg usage × avg lead) · Statistical: z × σ × √lead time
Economic Order Quantity	EOQ = √(2DS / H)
Days Inventory Outstanding	DIO = average inventory ÷ COGS × 365
Stock Coverage	Coverage = stock ÷ daily sales
Inventory Holding Cost	Holding cost = inventory value × carrying rate
Inventory Shrinkage	Shrinkage rate = Value of missing inventory ÷ Recorded inventory or sales × 100
Inventory Value	Value = Σ quantity × unit cost