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Warehouse and inventory, Advanced
Safety Stock
Buffer stock that protects against demand & lead-time variability
Formula: safety_stock = z × σ × sqrt(L)
Safety Stock = Z × σ × √L. Z is the service-level z-score (1.65 = 95%, 2.33 = 99%), σ is daily demand standard deviation, L is lead time in days.
Inputs
Results
Safety Stock
39.6 units
Recommended next actions
- →Z=1.65 → 95% service, Z=2.33 → 99%
- →Recompute monthly as demand variability changes
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Send the calculation to your inbox or book a review if the numbers point to cost, compliance, or uptime risk.
Formula
safety_stock = z × σ × sqrt(L)Worked example
Inputs
z_score1.65
demand_std_dev8
lead_time9
Outputs
safety_stock39.6
Use for estimation. Verify safety-critical calculations with qualified review.