Rule of 72

If you are interested in learning how to compound interest, the Rule of 72 is something to keep in mind. With the ability to determine interest rate growth, you can decide if a potential investment is good or bad for your portfolio.

The Rule of 72 is simple to understand. If you want to find how long it will take to double your money, you simply divide the interest rate into 72. For instance, the time it takes to double your money at six percent interest can be found by dividing 6 into 72 for a total of 12 years.

Interest Rate:	%

Years Required for Principal to Double
Exact Answer:
Rule of 72 Estimate:

The calculator assumes that interest is being compounded annually.

After using the calculator, it is easy to see the extreme accuracy of the Rule of 72. As long as you keep interest rates below 20 percent, the accuracy level will remain high.

In addition to figuring how long it will take to double your money, the calculator also allows you to work backwards to determine the interest rate needed to achieve a particular savings goal.

Years to double your investment

Required Interest Rate
Exact Answer:	%
Rule of 72 Estimate:	%

Rule of 72

Years Required for Principal to Double

Required Interest Rate