Rule of 72
A rough estimate of the time needed to double.
Your numbers
Enter your numbers to see the result.
A rough estimate of the time needed to double.
Enter your numbers to see the result.
Approximate doubling time = 72 ÷ annual percentage return. This is a shortcut for steady compound growth, not a forecast of investment performance.
These sample values illustrate the calculation. Use your own numbers in the calculator for your result.
Rates, fees and contribution schedules are the assumptions you enter. This estimate does not include changes you have not entered.
Educational estimate only. This is not personalized financial, investment or tax advice.