How it works
Average demand during a fixed lead time is combined with separately chosen safety stock. This form solves for lead time; enter the known quantities in Reorder stock level, Average daily demand, Safety stock.
Inputs and units
| Input | Example value | What to enter |
|---|---|---|
| Reorder stock level | 520 | Formula symbol: r. Enter a numeric value. Use a non-negative value. |
| Average daily demand | 20 | Formula symbol: d. Enter a numeric value. Must be greater than zero. |
| Safety stock | 120 | Formula symbol: s. Enter a numeric value. Use a non-negative value. |
Worked example
Show example inputs and results
This example is generated by the same calculation engine using the starting values in the form. Your own inputs produce your own result.
- Reorder stock level
- 520
- Average daily demand
- 20
- Safety stock
- 120
Complete example results
- Lead time
- 20 d
Reading the result
The result solves for lead time from the entered quantities. Check the result unit and the formula conditions before using it.
Questions and answers
Can I use the example values for my own calculation?
The example values illustrate the calculation. Replace every input with your own information, especially dates, rates and the selected operation.
When can I use the lead time result?
Daily demand and lead time must use the same day convention. Safety stock and supplier lead time are not estimated by this tool.
Why are some results rounded?
Results display up to 8 decimal places. Calculations use the unrounded values; very small values use scientific notation. JavaScript floating-point arithmetic can introduce tiny rounding differences.
Are my inputs sent to a server?
The calculator processes inputs in your browser. Its code does not send your values to a server.
Method sources: live.ocw.mit.edu