📦 Inventory Management
Inventory Requirement Calculator
Calculate safety stock, reorder point, EOQ, and optimize your inventory levels.
Average Daily Demand
units
Average units sold per day
Lead Time
days
Days from order placement to delivery
Service Level
%
Desired in-stock probability
Demand Variability (Std Dev)
units
Standard deviation of daily demand
Ordering Cost
$
Cost per purchase order
Holding Cost
$
/unit/yr
Cost to hold one unit for one year
Stock
0%
Reorder Point
0 units
order when stock reaches this level
Safety Stock
0 units
EOQ
0 units
Max Inventory
0 units
Service Level
0%
📐 Inventory Formulas
Safety Stock = Z × σ_d × √LT
Safety Stock
ROP = d × LT + Safety Stock
Reorder Point
EOQ = √(2DS / H)
Economic Order Quantity
Max Inv = ROP + EOQ
Max Inventory
📊 Inventory Breakdown
| Metric | Value | Formula |
|---|
How the formula works
Safety Stock = Z × σ_d × √LT | ROP = d × LT + SS | EOQ = √(2DS/H)
- Safety Stock = Buffer stock to protect against demand variability
- Z-Score = Service level factor (1.645 for 95%, 2.33 for 99%)
- Reorder Point (ROP) = Stock level that triggers a new order
- EOQ = Economic Order Quantity (balances ordering and holding costs)
- Max Inventory = ROP + EOQ (peak stock level)