Reorder Point Calculator – Inventory Control
Free Reorder Point Calculator. Know exactly when to reorder inventory and prevent stockouts.
Reorder Point Calculator – Inventory Control
Free Reorder Point Calculator. Know exactly when to reorder inventory and prevent stockouts.
Generated: 2/22/2026, 12:34:01 AM | AskSMB.io
Calculate Reorder Point
Inputs
Average number of units sold or used per day
Number of days between placing and receiving an order
Extra inventory kept as a buffer
Results
Average daily usage must be greater than zero
How the Reorder Point Calculator Works
What is Reorder Point?
Reorder point (ROP) is the inventory level that triggers a new purchase order. It's calculated to ensure you place orders with enough time for new stock to arrive before current inventory runs out. Think of it as your inventory alarm system — when stock hits this level, it's time to reorder. The reorder point accounts for both the time it takes to receive new inventory (lead time) and your average daily usage during that period.
Why Reorder Point Matters
- •Prevent Stockouts: Never run out of inventory and lose sales
- •Automate Ordering: Set triggers for automatic reordering
- •Maintain Service Levels: Keep customers satisfied with consistent availability
- •Optimize Cash Flow: Order at the right time, not too early or late
Formula
Average Daily Usage = Units sold or used per day
Lead Time = Days between order placement and receipt
Safety Stock = Buffer inventory for unexpected demand or delays
Example Calculation
Demand during lead time = 20 × 7 = 140 units
Reorder point = 140 + 30 = 170 units
Reorder Point vs EOQ
Reorder point and Economic Order Quantity (EOQ) serve different purposes but work together perfectly. EOQ tells you how much to order (the optimal quantity that minimizes costs), while reorder point tells you when to order (the inventory level that triggers an order). Use EOQ to determine your order size, and use reorder point to determine your order timing. Together, they create an efficient, automated inventory management system.
The Role of Safety Stock
Safety stock is your insurance policy against uncertainty. It protects you from:
- ✓Unexpected demand spikes (seasonal rushes, viral trends)
- ✓Supplier delays (shipping problems, production issues)
- ✓Quality issues requiring replacement orders
- ✓Natural disasters or other supply chain disruptions
A good rule of thumb: safety stock should be 10-20% of your demand during lead time for stable products, or 25-50% for products with variable demand or unreliable suppliers.
How to Reduce Stockouts
- 1.Calculate accurate reorder points based on real usage data, not estimates
- 2.Maintain appropriate safety stock for high-demand or critical items
- 3.Monitor supplier performance and adjust lead times as needed
- 4.Review reorder points regularly (monthly or quarterly)
- 5.Use inventory management software to automate reorder alerts
- 6.Diversify suppliers to reduce dependency on single sources
Frequently Asked Questions
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