Inventory Safety Stock
Estimate a demand-variation buffer for fixed lead time.
Your numbers
Safety stock
Independent daily demand with stable variance and fixed lead time. Choose the service factor separately; this is not a guaranteed fill rate.
Scenario comparison
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Formula
Use SS = zσ√L. z is the chosen service factor, σ is the standard deviation of daily demand, and L is fixed lead time in days. Daily demand is assumed independent with stable variance.
Estimate a demand-variation buffer for fixed lead time.
Worked example
- Service-factor z
- 1.65
- Daily demand standard deviation
- 10
- Fixed lead time in days
- 9
- Safety stock
- 49.5 units
Scope and limitations
Independent daily demand with stable variance and fixed lead time. Choose the service factor separately; this is not a guaranteed fill rate.
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Formula version: 397103b95ec8 · Example checked: