Reorder Point Calculator
Calculate Reorder Point step by step: reorder point = average daily demand × lead time + safety stock.
In short
Formula: Reorder point = average daily demand × lead time + safety stock.
What this calculator does
Calculate Reorder Point step by step: reorder point = average daily demand × lead time + safety stock. Worked example, questions and limitations included.
Use it to turn Average daily demand, Lead time, Safety stock (enter 0 if none) into a checked result you can compare, copy, or rerun with different assumptions.
The page shows the formula, a numeric worked example, and the assumptions that affect this inventory calculation.
Inputs and what they mean
- Average daily demand
- — number value.
- Lead time
- — number value.
- Safety stock (enter 0 if none)
- — number value.
How to use it
- Enter each value in the unit shown next to the box (use the unit converter first if your numbers are in other units).
- Check the breakdown to see every intermediate step.
- Read the limitations before relying on the result.
Formula
Order point definition from the ASCM (APICS) dictionary.
Safety stock is entered by you — none is assumed. Use the safety stock calculator to work it out.
Demand and lead time must use the same time unit.
Reorder point = average daily demand × lead time + safety stock.
Inputs used: Average daily demand, Lead time, Safety stock (enter 0 if none).
Worked example
Spare part
- 40 × 7 = 280 units.
- 280 + 100 = 380 units.
Reading the result
The headline figure is the main answer. Any breakdown underneath shows the parts that make it up, so you can check the working and see what changes when you adjust an input.
Limitations and assumptions
- Uses average demand only.
- Assumes lead time is as entered.
- Continuous review assumed.
- Results are planning estimates built only from the figures you enter. No prices, rates, demand patterns or service levels are built in, and the results are not supplier quotes or carrier rates.
- The result depends on the values you enter for this reorder point calculator; it does not supply missing rates, rules, prices, dates, or assumptions for you.
Common questions
Should I include stock already on order?
Compare the reorder point with inventory position (on hand + on order − backorders), not just on-hand stock. Check the formula, example, and limitations on this page before using the result for a real inventory decision.
Why is no safety stock filled in?
The right buffer depends on your demand variability and the service level you choose. We never assume one.
Weekly figures?
Fine, as long as demand is per week and lead time is in weeks. Check the formula, example, and limitations on this page before using the result for a real inventory decision.
How do I use the Reorder Point Calculator?
Enter the required values for Average daily demand, Lead time, Safety stock (enter 0 if none). The calculator applies the formula on this page and shows the main result with any supporting breakdown so you can check the arithmetic.
What formula does the Reorder Point Calculator use?
Reorder point = average daily demand × lead time + safety stock. The visible formula section above lists the calculation path and the edge cases the page handles, so the result can be checked without relying on the form alone.
Can the Reorder Point Calculator be used for exact decisions?
Use it as a calculation aid, not as a substitute for checking the underlying rule, contract, policy, or professional advice that applies to your situation. When a result depends on local rules, personal details, prices, or dates, enter those values yourself and confirm them before acting.
Related tools
Calculate EOQ step by step: EOQ = √(2 × annual demand × cost per order ÷ holding cost per unit per year).
Calculate Safety Stock with your chosen method: fixed days of cover, z × σd × √L, or combined demand and lead-time variability.
Calculate Inventory Turnover step by step: cost of goods sold ÷ average inventory.
Calculate Inventory Days step by step: average inventory ÷ cost of goods sold × days in period.
Calculate Carrying Cost step by step: capital cost + storage + insurance and taxes + obsolescence and shrinkage.
Calculate Stock Coverage step by step: (on hand + on order) ÷ expected daily demand.