Rule of 72 Calculator
Estimate how long it will take to double your investment
The Rule of 72 is a quick, useful formula that is popularly used to estimate the number of years required to double the invested money at a given annual rate of return.
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How It Works
Years to Double ≈ 72 / Annual Rate of Return. For example, at 6%, it takes 72/6 = 12 years.
Tips & Best Practices
- •The Rule of 72 is an approximation. It is most accurate for interest rates between 6% and 10%.
- •For continuous compounding, the Rule of 69.3 is more accurate.
Frequently Asked Questions
Why 72?
72 is used because it has many divisors (2, 3, 4, 6, 8, 9, 12, etc.), making it easy to calculate mentally.
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