Free tool

Safety stock calculator

The buffer that keeps you selling when demand spikes and the delivery is late at the same time — from your own maximums and averages.
Safety stock
192 units
Reorder point with it
360 units
Days of average sales
16 days

How it is calculated

Safety stock = (maximum daily sales × longest lead time) − (average daily sales × average lead time).

This is the simple maximum-minus-average method. It assumes the worst day and the worst delay happen together, so it errs on the safe side.

Questions

Is there a more precise method?

The statistical method uses the standard deviation of demand and a service-level factor. It needs more history; the maximum-minus-average method is a sound start for most small shops.

Can safety stock be too high?

Yes. It ties up cash and shelf space, and slow-moving stock risks becoming dead stock. Keep it highest on the products that sell fastest and earn most.

How often should I recalculate?

Whenever a supplier’s lead time changes, and before each season.

If you run WooCommerce

StockPulse tracks how fast each WooCommerce product sells, which is the average and maximum daily demand this formula needs. StockPulse is our plugin; the calculator above works the same whether you use it or not.

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