Operations Metric

Out-of-Stock Rate

The Out-of-Stock Rate indicates what percentage of SKUs (product variants) are currently unavailable.

Formula
OOS Rate = (Unavailable SKUs / Total SKUs) × 100

Calculate Out-of-Stock Rate

Enter your values to calculate your out-of-stock rate.

Out-of-Stock Ratecalculate
OOS Rate = (Out-of-Stock SKUs / Total SKUs) × 100
Result:

Out-of-Stock Rate is a critical indicator of missed sales opportunities. Every unavailable product means potentially lost revenue.

Good sign

An OOS rate below 5% is considered good. It shows that your inventory planning reliably meets demand.

Warning sign

A high OOS rate leads to lost revenue, customer defection to competitors and negative customer experiences.

Always consider OOS rate in context with inventory turnover. A rate that's too low may indicate inefficient capital allocation.

Industry Benchmark
Target (all industries) < 5%
Excellent < 2%
Acceptable 5–8%
Critical > 10%
  • Implement automatic reordering when stock falls below safety levels
  • Use demand forecasting with machine learning for more precise predictions
  • Build strategic safety stock for bestsellers
  • Monitor OOS rate in real-time via a dashboard
  • Establish clear escalation processes for critical OOS situations
  • No differentiation by product importance (ABC classification)
  • Supplier issues not managed proactively
  • Seasonal peaks underestimated in planning
  • No alternative supply sources for critical products

What does Out-of-Stock Rate mean for your online store?

Out-of-Stock Rate (OOS Rate) is one of the most critical operations metrics in e-commerce. It shows what percentage of your assortment is currently unavailable. Every 'Sold Out' sign is a missed sales opportunity – and worse: a reason for customers to switch to competitors.

Why Out-of-Stock Rate matters

Studies show that 21-43% of customers buy the product from a competitor when faced with an out-of-stock. Another 27% don't buy at all. This means: out-of-stocks don't just cost individual sales, they jeopardize the entire customer relationship.

For a store with 10,000 SKUs and 8% OOS rate, 800 products are unavailable. With an average of 5 missed sales per day per SKU at $50 AOV, that's $200,000 in lost revenue per day.

How to reduce your Out-of-Stock Rate

There are proven strategies to sustainably reduce OOS rate:

  1. 1 Automated Reordering: Set up automatic order triggers when stock falls below defined minimum levels. This eliminates human delays.
  2. 2 Precise Demand Forecasting: Use historical data, seasonality and external factors for reliable sales forecasts.
  3. 3 Supplier Diversification: Have alternative supply sources for your top sellers. A single supplier failure shouldn't cause OOS.
  4. 4 Real-time Monitoring: Monitor your inventory in real-time and react proactively to developing OOS situations.

Out-of-Stock in context with other KPIs

Out-of-Stock Rate exists in tension with Inventory Turnover. Very high inventory turnover can lead to higher OOS rates, while excessive safety stock worsens turnover. The art lies in finding the balance.

Analyze your OOS rate by product categories, suppliers and time periods. Patterns often emerge that point to systematic issues – such as certain suppliers with frequent delays or categories with hard-to-predict demand.

Reduce your Out-of-Stock Rate?

Together we analyze your inventory data and identify the biggest levers to prevent stockouts.

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