Rule 69 Time to Double Calculator
This calculator uses Rule 69 to estimate how long it will take to double an investment with continuous compounding. Simply input the annual interest rate, and this tool will calculate the approximate number of years it will take to achieve your investment goal.
Calculate the Time to Double Your Investment Using Rule 69
Rule 69 Formula for Time to Double
$$\text{Time to Double} = \frac{69}{r}$$
Where:
- r – Annual interest rate (as a percentage)
The Rule of 69 is a quick and convenient way to estimate the time required to double your money under continuous compounding conditions. It’s widely used in personal finance, investing, and economic forecasting. Unlike the Rule of 72, which is commonly used for basic interest compounding, the Rule of 69 provides a more accurate estimation when dealing with continuous compounding.