Sales forecast calculator
Project your monthly revenue over several months by applying a compound growth rate and visualize the trajectory.
Enter your data to generate the forecast.
Revenue for the current month or last complete month.
Expected growth rate each month. Use negative values to model decline.
Forecast duration (1 to 60 months).
Enter your data and click Calculate to see your results.
Understanding sales forecasting
Compound growth
Compound growth applies the growth rate on the previous month's base, not the initial month. This is the most realistic method to model an e-commerce trajectory.
Choosing the right rate
Base your rate on the average of the last 6 months. Adjust for seasonality, planned launches and scheduled marketing investments.
Multiple scenarios
Run three scenarios: pessimistic (-2%), realistic (+3 to 5%) and optimistic (+8 to 10%). This lets you anticipate cash and hiring needs.
Model limits
A linear model ignores seasonality, launch spikes and external events. Use it as a baseline, then manually adjust atypical months.
Frequently asked questions
How to estimate a realistic growth rate?+
Calculate the average growth of your last 6 months. For a young growing shop, 5-15% per month is common. For a mature shop, 1-3% is more realistic.
What is the difference between simple and compound growth?+
Simple growth always adds the same amount (e.g., +1000 EUR per month). Compound growth applies a percentage on the previous month, creating an exponential effect.
How to integrate seasonality?+
Apply a monthly coefficient to the linear output (e.g., +30% in November, -20% in February) based on your historical data. Fullmetrix automates this with real data.
What time horizon should I forecast?+
3 months for operations (cash, stock), 12 months for budgeting, 36 months for strategy. The longer the horizon, the higher the uncertainty.
How to track forecast vs actual?+
Track the variance between forecast and actual every month. A variance of +/- 10% is normal; beyond that, revisit assumptions (growth, seasonality, investments).
How does Fullmetrix help forecast sales?+
Fullmetrix uses your historical data to automatically calculate trend growth, seasonality and projected run rate, with alerts on variances.
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