Rule of 72
A quick and useful formula to estimate how many years it takes for your money to double.
%
1%30%
Simple Formula
72 ÷ Annual Rate = Years to Double. This is a mental shortcut for exponential growth.
Inverse Use
Want to double in 10 years? 72 ÷ 10 = 7.2. You need a 7.2% annual return.
Accuracy
Most accurate for interest rates between 6% and 10%. Higher or lower rates may deviate slightly.
Calculation Time: 06:15:49 12/04/2026
Simulation ID: CALC-R72-1775974549130
Rule of 72 Report
Time to Double
9.0
Years
With a 8% annual return, your investment will double approximately every 9.0 years.
The Rule of 72 is an approximation. Actual doubling time may differ.
Input Summary
Expected Annual Return (%)8%
Time to Double9.0 Years
This report is auto-generated by FiMo Professional. For informational purposes only.