# What is Demand Forecasting?

What is Demand Forecasting? Using historical data to predict sales volume. Enables ordering the right amount of inventory at the right time.

## How it works in practice

Demand forecasting is the difference between a stockout during a holiday and operational calm.

## Related metrics

- Lead Time — forecast × lead time = when to order
- Inventory Management — forecasting is the foundation
- Seasonality — a key factor
- Safety Stock — a cushion against forecasting errors

## Common misconception

'Forecasting requires complex BI.' A simple spreadsheet works: sales for month X × 3 years × growth factor ± events.

## How to fix it

Not accurate? (1) account for seasonality from the same month last year, (2) one-time events that skewed data, (3) compare forecast vs. actual monthly.

## Real-world example

A toy store: flat order quantities caused a stockout in December (340% demand) and excess in January (40% demand). A 3-year analysis saved $18,000/year.

## Where to start

A basic spreadsheet: month X × 3 years → average → × growth factor. 3 hours of work.

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Category: Operations · From the [Jimmy OS KPI Glossary](https://jimmy-os.com/glossary/kpi.md) · Source page: https://jimmy-os.com/glossary/kpi/demand-forecasting