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Rule of 72 Calculator

Quickly estimate how long it will take for your investment to double with our easy-to-use Rule of 72 Calculator.

Calculate How Long It Takes to Double Your Investment

Sensitivity Analysis

What is the Rule of 72?

The Rule of 72 is a simple formula used to estimate the number of years required to double the value of an investment at a fixed annual rate of return.

The formula is:

Years to Double = 72 / Interest Rate (%)

How to Use the Rule of 72 Calculator

  • Enter the interest rate you expect to earn on your investment.
  • Enter the initial amount of money you plan to invest.
  • Click "Calculate" to see how many years it will take for your investment to double.

The calculator will provide a quick estimation, but remember that it assumes a fixed rate of return. Actual investment growth can vary due to market conditions.

Formula and Calculation Examples

The Rule of 72 formula is straightforward:

Years to Double = 72 / Interest Rate (%)

For example, if your expected annual interest rate is 8%, the calculation would be:

72 / 8 = 9 years

This means it would take approximately 9 years for your investment to double at an 8% interest rate.

Frequently Asked Questions (FAQs)

What is the Rule of 72?

The Rule of 72 is a quick and easy way to estimate how long it will take for an investment to double in value based on a fixed annual interest rate.

How accurate is the Rule of 72?

The Rule of 72 provides a rough estimate, but it may not be completely accurate, especially for very high or low interest rates. It is most accurate for interest rates between 6% and 10%.

Can the Rule of 72 be used for other types of growth?

Yes, the Rule of 72 can be applied to any situation where something grows at a compound rate, such as population growth, inflation, or the decay of radioactive materials.