Safety Stock Calculator

Calculate safety stock accounting for demand variability and lead time variability. All calculations run in your browser; your data is never sent to any server.

Parameters

Average units sold per day.

Daily demand variability.

Average days between placing an order and receiving it.

Variability in delivery time.

Target probability of not running out of stock.

Recommended safety stock
334units

Lead time variability dominates the safety stock.

z (service level)
1.6
σ during lead time
202.8
Standard deviation by source
AI interpretation

A read of the result like a consultant would give: what it means, what drives it, and one recommendation.

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Preguntas frecuentes

How is safety stock calculated?
With the general formula SS = z · √(LT · σ_demand² + demand² · σ_leadTime²), where z is the normal quantile of the service level. It combines the variability of demand and of lead time.
What service level should I use?
90–95% is common for most products; raise it to 98–99% for critical items. The higher the service level, the higher the safety stock.