Driver-based forecasting builds revenue from the operational inputs behind it rather than from last year’s totals. Set volume, growth, conversion, price and seasonality to produce a monthly revenue forecast you can explain driver by driver.
How it works
Forecast revenue from the operational drivers behind it: starting volume, growth, conversion rate, average price, annual price increases and monthly seasonality.
Volume(t) = Starting volume × (1 + monthly growth)^t × Seasonality index(month)
Conversions(t) = Volume(t) × Conversion rate
Price(t) = Average price × (1 + annual increase)^floor(t ÷ 12)
Revenue(t) = Conversions(t) × Price(t)Common uses
- Annual budgets and rolling forecasts built from operating metrics
- Sales and marketing funnel planning
- New service-line and product launch projections
Worked example
The calculator above opens with this example. Change any input to see the results update instantly, or select Reset to return to these figures.
| Starting monthly volume (leads, visits, referrals) | 40,000 |
| Volume growth per month | 1.5% |
| Conversion rate | 3.2% |
| Average price per conversion | $185 |
| Annual price increase | 3% |
| Horizon | 12 months |
| First forecast month | 2027-01 |
| Seasonality indices, Jan–Dec (optional) | 0.92 0.88 1.02 1.00 1.04 0.98 0.95 0.97 1.03 1.06 1.05 1.10 |
| Revenue, first 12 months | $3,095,255 |
| Average monthly revenue | $257,938 |
| Total conversions | 16,731 |
| Revenue per unit of volume | $5.92 |
Peak month: Dec 2027 at $306,832. Seasonality indices were rescaled to average exactly 1.00.
Interpreting the results
- Tie each driver to an operational source the business already tracks, so variances can be explained by driver.
- Calculate seasonality indices from two or more years of history; the Seasonality Index Calculator can produce them.
- Test the forecast by flexing one driver at a time; conversion and price usually carry the most risk.
Frequently asked questions
What is driver-based forecasting?
Driver-based forecasting models financial results as the product of operational drivers, such as leads, conversion rates and average price. When actual results differ from the forecast, the variance can be traced to the specific driver that missed.
How many drivers should a revenue model use?
Use the smallest set of drivers that explains most of the variation in revenue and that the business can measure reliably every month. Three to six drivers is typical; adding more increases complexity without improving accuracy.
Where do the seasonality indices come from?
Calculate them from at least two years of monthly history using the ratio-to-moving-average method. The Seasonality Index Calculator on this site produces indices you can paste directly into this model.
Related calculators
- Rolling Forecast Builder: 12- to 24-month rolling forecast from monthly actuals using four methods.
- Seasonality Index Calculator: Monthly or quarterly seasonal indices and the deseasonalized series.
- Scenario & Sensitivity Analyzer: Base, upside and downside profit with a tornado ranking of drivers.
- Monte Carlo Profit Simulator: Simulate thousands of profit outcomes with P10/P50/P90 and probability of loss.
- Moving Average & Exponential Smoothing Forecast: SMA, WMA, simple, Holt and Holt-Winters forecasts with fit statistics.