Input Values
Enter your interest rate
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The Rule of 72 Formula
Years to Double = 72 ÷ Interest Rate
This is an approximation that works best for rates between 6% and 10%.
Double In
6 yrs
Rule of 72
Exact Double
6.1 yrs
Precise calculation
Triple In
9.7 yrs
Quadruple In
12.2 yrs
Future Value Projections
How ₹1,00,000 grows at 12% annual return
| Years | Value | Growth Multiple |
|---|---|---|
| 1 | ₹11,200 | 1.12x |
| 5 | ₹17,623 | 1.76x |
| 10 | ₹31,058 | 3.11x |
| 15 | ₹54,736 | 5.47x |
| 20 | ₹96,463 | 9.65x |
| 25 | ₹1,70,001 | 17x |
| 30 | ₹2,99,599 | 29.96x |
| 40 | ₹9,30,510 | 93.05x |
| 50 | ₹28,90,022 | 289x |
How the Rule of 72 Works
The Rule of 72 is a quick mental math shortcut to estimate how long an investment will take to double in value given a fixed annual rate of return.
For example, if you invest at 12% annual return, your money will approximately double in 6 years.
Note: The Rule of 72 is most accurate for interest rates between 6% and 10%. For other rates, the exact compound interest formula gives more precise results.