The Rule of 72 is a classic mental math shortcut used by investors to quickly estimate how many years it will take to double an investment at a given annual rate of return.
$$\text{Years to Double} \approx \frac{72}{\text{Annual Interest Rate}}$$
Use this quick calculator to estimate your money-doubling timeline across different expected returns, or calculate the annual rate required to double your money within a specific timeframe.
Rule of 72 Calculator
Estimate how long it takes to double investment value.
Result Summary
Return Rate-
Approx. Years to Double-
Quick Estimate-
These results are indicative and may vary based on market returns, charges, taxes, and other assumptions.