Need to project compound growth? This exponential extrapolation calculator fits an exponential curve to your data and forecasts future values assuming percentage-based growth continues.
Exponential Extrapolation Calculator
Using the calculator
Enter at least two data points with positive Y values, then specify your target X. The calculator fits an exponential curve and projects the Y value.
You'll see the R² fit quality and the equation y = a × e^(bx) being used.
Heads up: Exponential fits require all Y values > 0 (zeros and negatives can't be log-transformed). And the farther you project, the less reliable the estimate.
What is exponential extrapolation?
Exponential extrapolation assumes growth by a constant percentage rather than a constant amount. The formula:
y = a \times e^{bx}Where a is the initial value and b is the growth rate. Positive b means exponential growth; negative b means exponential decay.
When to use exponential extrapolation
Exponential extrapolation works best for:
- Compound growth: Investments, savings, debt
- Population: Bacterial growth, demographic projections
- Decay: Radioactive decay, depreciation
Great for compounding and decay; not great for straight-line trends.
If your data shows constant absolute change (not percentage), use linear extrapolation instead.
