Demand Forecaster
Enter 12 months of sales history and get AI-quality forecasts — trend detection, auto-calculated seasonality, anomaly flags, and three projection scenarios.
Historical Sales Data
Enter your monthly order/sales volumes for the last 12 months (Jan–Dec or any 12 consecutive months). At least 3 values required for analysis.
Fill in at least 3 months of historical sales data above to auto-calculate trend, seasonality, and generate your 3-scenario forecast.
How This Forecaster Works
This tool uses statistical methods from actual demand planning practice — no black boxes, no assumptions baked in. Everything is calculated from your data.
Linear Regression (Trend Detection)
The tool fits a least-squares regression line to your historical data. The slope of this line is your organic monthly growth rate — positive means growing, negative means declining. This is used as the baseline for all three forecast scenarios.
Seasonality Index
Each month's seasonality index is the ratio of its actual value to the trend-line value at that point, normalised so the average index = 1.0. An index of 1.3 means that month typically runs 30% above the trend — capturing real patterns from your own data rather than generic assumptions.
Three Scenarios
- Conservative — Trend line only. Best for pessimistic planning and minimum inventory requirements.
- Moderate — Trend × seasonality index. The most realistic scenario for standard inventory planning.
- Aggressive — Trend × seasonality × small compounding growth factor. Useful for capacity planning and upper-bound buffer stock calculations.
Anomaly Detection
Months where actual sales deviate more than 2 standard deviations from the trend line are flagged as anomalies. These often represent flash sales, stockouts, or external disruptions — and knowing about them helps you avoid letting outliers skew your forecast.
How Nventory Helps
Nventory tracks your sales velocity across every channel in real time and generates demand forecasts automatically. Instead of maintaining spreadsheets, Nventory surfaces reorder recommendations, flags seasonal trends, and helps you plan purchasing decisions with confidence — reducing both stockouts and excess inventory carrying costs.
Want AI-powered demand forecasting across all your channels?
Frequently Asked
Questions
Everything you need to know about this tool, how it works, and what to expect from the results.
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Contact SupportIt projects your monthly order volumes for the next 12 months based on historical sales data, growth trends, and seasonal patterns. Use the forecasts to plan purchasing, staffing, and inventory allocation.
Enter monthly sales figures for at least the past 6 to 12 months, set your expected growth rate, and adjust seasonal factors for months with higher or lower demand. The tool outputs a 12-month forecast with projected quantities.
Yes. All forecasting calculations run entirely in your browser. No sales history or projections are sent to any server.
Accuracy depends on the quality and quantity of your historical data. More months of history produce better trends. The tool uses straightforward growth and seasonality models, which work well for stable products but may not capture sudden market shifts.
Combine the monthly projections with your supplier lead times to determine when to place orders. Layer in safety stock calculations for demand variability. Review and adjust the forecast monthly as actual sales data comes in.
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