Rule of 72 Calculator
The magic number to know exactly when your money doubles.
Time to Double
6 Years
Exact Calculation
6.1 Years
Formula Used
72 ÷ Rate
Doubling Timeline
What is the Rule of 72?
It is a mental shortcut. Instead of complex compound interest formulas, you just divide 72 by your interest rate. The answer tells you how many years it takes for your investment to double.
The Calculation
72 ÷ Interest Rate = Years to Double
Example: At 12% returns, 72 ÷ 12 = 6 Years.
Why it matters
It helps you realistic goals. If you want to double your money in 3 years (72 ÷ 3 = 24), you need 24% returns, which is huge risk.