Rule of 72 Calculator
The Rule of 72 is a quick mental-math shortcut for estimating investment doubling time. Divide 72 by your annual rate of return to see approximately how many years until your money doubles.
Inputs
%
$
Results
Rule of 72 Estimate
9.0 years
Exact Doubling Time
9.0 years
Doubled Amount
$20,000
Time to 4x
18.0 years
Growth Milestones
| Milestone | Time |
|---|---|
| 2x ($20,000) | 9.0 yrs |
| 4x ($40,000) | 18.0 yrs |
| 8x ($80,000) | 27.0 yrs |
| 16x ($160,000) | 36.0 yrs |
Frequently Asked Questions
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