Rule of 72

Rule of 72 Calculator

This calculator estimates the number of years required to double your money at a given annual fixed interest rate.

Use Cases

• Financial Planning: Quick mental estimates for investment growth.
• Education: Teaching compound interest concepts.
• Inflation: Estimating when prices will double.

Formula

$$\text{Years to Double} \approx \frac{72}{\text{Annual Interest Rate}}$$

Note: The interest rate should be entered as a percentage (e.g., 8 for 8%).