Enter the annual interest rate into the calculator to determine the time it takes for an investment to double using the Rule of 144.

Rule Of 144 Formula

The following formula is used to calculate the time it takes for an investment to double using the Rule of 144.

T = 144 / r

Variables:

  • T is the time it takes for the investment to double (in years)
  • r is the annual interest rate (in percentage)

To calculate the time it takes for an investment to double, divide 144 by the annual interest rate. The result will be the number of years it will take for the investment to double.

What is a Rule Of 144?

The Rule of 144 is a simple formula used in finance to estimate the number of years it will take for an investment to double in value at a fixed annual rate of interest. By dividing 144 by the annual rate of return, investors can get a rough estimate of how many years it will take for the initial investment to duplicate itself. This rule is a simplified version of the more complex and precise formula used in finance to calculate compound interest.

How to Calculate Rule Of 144?

The following steps outline how to calculate the Rule of 144.


  1. First, determine the annual interest rate (r) in percentage.
  2. Next, use the formula T = 144 / r to calculate the time it takes for the investment to double (T) in years.
  3. Finally, calculate the Rule of 144.
  4. After inserting the variables and calculating the result, check your answer with the calculator above.

Example Problem:

Use the following variables as an example problem to test your knowledge.

Annual interest rate (r) = 6%

Time it takes for the investment to double (T) = ?