Rule of 72 Calculator
Use the Rule of 72 to quickly estimate doubling time โ or what rate you need to double in a specific timeframe.
Your Monthly EMI
โน116
Principal
โน10,000
Total Interest
โน3,933
Total Payable
โน13,933
Breakdown
Principal: โน10,000 (72%)
Total Interest: โน3,933 (28%)
Interest-to-Principal: 39.3%
๐ Interactive EMI Breakdown
Principal vs Interest
Principal: โน10,000
Interest: โน3,933
Year-by-Year Payment Split
Loan Scenario Comparison
| Metric | Your plan | +1% Interest (8.0%) | +12 Months (132mo) |
|---|---|---|---|
| Monthly EMI | โน116 | โน121 โ โน5 | โน109 โ โน7 |
| Total Interest | โน3,933 | โน4,559 โ โน626 | โน4,367 โ โน434 |
| Total Payable | โน13,933 | โน14,559 | โน14,367 |
What Is the Rule of 72?
Mental math shortcut: Years to Double โ 72 / Rate. Accurate for rates between 2% and 15%.
Quick Reference
| Rate | Rule of 72 | Exact |
|---|---|---|
| 3% | 24.0yr | 23.4yr |
| 5% | 14.4yr | 14.2yr |
| 7% | 10.3yr | 10.2yr |
| 10% | 7.2yr | 7.3yr |
| 12% | 6.0yr | 6.1yr |
Reverse
Double in 5 years? Rate โ 72/5 = 14.4%
Practical
- S&P 500 ~10%: doubles every 7.2yr
- Inflation 3%: costs double every 24yr