Rule of 72: Years to Double at Various Annual Returns
Using the Rule of 72 to estimate how many years an investment takes to double at various annual rates of return.
| Annual return | Approx. years to double (72÷r) |
|---|---|
| 2% | 36 years |
| 3% | 24 years |
| 4% | 18 years |
| 6% | 12 years |
| 8% | 9 years |
| 9% | 8 years |
| 12% | 6 years |
Method & sources
Years to double ≈ 72 ÷ annual return (in percent). This is a mental-math approximation; it ignores the exact compounding solution, taxes and fees, and the error grows slightly at higher rates.
Source: https://www.sec.gov/investor/projectchange/creating_choices.shtml
Retrieved: 2026-09
FAQ
- What does "Rule of 72: Years to Double at Various Annual Returns" cover?
- It covers 2%, 3%, 4%, 6%, 8%, 9%, 12%, compared across: Annual return, Approx. years to double (72÷r).
- What are the sources and methodology?
- Years to double ≈ 72 ÷ annual return (in percent).
- When was this data last updated?
- The data was retrieved/updated on 2026-09.