The Rule of 72 is a shortcut: Years to double ≈ 72 ÷ annual return %. At 8% return, money doubles in about 9 years. At 12%, about 6 years.
Quick examples
- FD at 7% → 72/7 ≈ 10.3 years
- Equity assumption 12% → 72/12 = 6 years
- Savings account 3% → 72/3 = 24 years
Limitations
Approximation only — compounding frequency and taxes change real outcome. Use FD Calculator or CI Calculator for exact figures.
Try Master Calc Rule of 72 Calculator for instant doubles and reverse math (what rate needed to double in N years).
Disclaimer: Returns assumed are illustrative.