INVESTING CHANNEL
Rule of 72 Calculator
Find out exactly how many years it will take to double your savings at a given interest rate.
Calculator Variables
Calculation Overview
Calculate how long it takes to double your money at a given interest rate using the mathematical Rule of 72.
Mathematical Model & Formula
t = 72 / r
Divides the constant 72 by the annual growth rate to approximate the doubling period of a compounding balance.
Variables Defined:
- t: Years required to double the investment value
- r: Annual interest rate percentage
Worked Example Scenario
Scenario: Investing at a 6% interest rate.
- t = 72 / 6 = 12
Result: It takes 12 years to double your capital.
Frequently Asked Questions
Is the Rule of 72 accurate?
Yes, it is highly accurate for common interest rates. For extremely high rates, 73 or 74 can be more precise.