Free inventory planning tool
Reorder Point Calculator
Estimate the stock threshold for a replenishment review. Enter daily demand, lead time, and your safety stock to see the calculation immediately. No signup required.
Your assumptions
The prefilled values are an example. Replace them with your own inputs.
Use a representative period and the same unit of stock throughout.
Include the time from placing an order until stock is available to sell.
Enter the buffer your team has chosen. This tool does not estimate it.
Use non-negative numbers up to 1,000,000, with up to three decimal places and a decimal point. Lead time must be greater than zero. Keep all time inputs in days.
Your reorder threshold
160 units
Rounded up to the next whole unit when needed.
- Expected demand during lead time
- 120 units
- Threshold before rounding
- 160 units
This is a planning threshold, not an order quantity. Before placing an order, review available stock, committed demand, usable inbound supply, and your purchasing policy.
The reorder point formula
Reorder point = average daily demand × lead time in days + safety stock.
In the fictional example, 12 units per day × 10 days + 40 buffer units = 160 units. The buffer is supplied by you; the calculator does not select a service level or predict demand.
The method is also explained in inFlow’s reorder point guide. Calculate separately for each SKU and location with consistent stock units.
Turn the number into a decision
A threshold is useful only alongside current records. An overdue shipment or a sudden demand change can invalidate the assumptions. This simple model does not guarantee stock availability.
Read the inventory replenishment guide for a worked review, then use the SOP template to document who checks the data and approves the next action.
Common questions
How is reorder point different from order quantity?
The reorder point helps identify when to review replenishment. Order quantity depends on a separate policy, available capacity, supplier constraints, and cost. This calculator does not compute it.
Can I use monthly demand?
Convert demand to units per day first using the period you actually measured. Mixing monthly demand with a lead time in days would produce the wrong threshold.
What if demand is seasonal or I review stock weekly?
Choose inputs that reflect the relevant demand period. Periodic review needs to consider the time until the next review as well as replenishment lead time; this calculator models the simple lead-time formula only.
Does this connect to my store or place an order?
No. It calculates from the numbers you type in this page. It does not read your store, update inventory, or place purchase orders.