A mental shortcut that makes compounding feel real.
Direct answer
The Rule of 72 says: years to double ≈ 72 ÷ annual rate of return. At 6 percent, money doubles in about 12 years. At 9 percent, about 8 years. It is an approximation, useful for quick comparisons.
Examples
| Annual rate | Years to double (72 ÷ rate) |
|---|---|
| 2% | 36 |
| 4% | 18 |
| 6% | 12 |
| 8% | 9 |
| 12% | 6 |
Uses
- Compare savings rates quickly.
- See what inflation does: at 3 percent, prices double in about 24 years.
- Understand how interest on debt grows if you do not pay it down.
Limits
It is an estimate. Returns on investments are not guaranteed and vary year to year.
Where Teyro fits
Teyro's Money Habits That Build Long-Term Wealth course turns this into short lessons you can play in a few minutes a day. It has 50 lessons, and you can start free.
The bottom line
A quick way to see why rate and time matter. For exact figures, use a calculator.
This is general education, not personal financial advice.
