The Rule of 72: How to Double Your Money with Compound Interest
Learn the simple Rule of 72 to quickly estimate how long it takes to double your investment.
The Rule of 72 Explained
The Rule of 72 is a simple way to estimate how long it takes to double your money at a given interest rate.
The Formula
Years to Double = 72 รท Interest Rate
Examples
| Interest Rate | Years to Double |
|---|---|
| 4% | 18 years |
| 6% | 12 years |
| 8% | 9 years |
| 10% | 7.2 years |
| 12% | 6 years |
Why It Works
The Rule of 72 is a mathematical approximation that works well for interest rates between 6% and 10%. It's derived from the natural logarithm of 2.
Practical Applications
- Retirement planning: Estimate portfolio growth
- Debt awareness: See how fast debt doubles
- Investment comparison: Quickly compare options
Use our Compound Interest Calculator for precise projections!