How to Use Investing Calculators Correctly (Avoid These Mistakes)
Avoid common calculator mistakes: wrong years, ignoring fees, mixing contributions, and confusing ROI vs CAGR. Learn how to input values correctly for real decisions.
The right tool with the wrong inputs still gives the wrong answer. Use these checks before trusting the result.
Common mistakes
- Using months as years
- Ignoring fees and inflation
- Mixing contributions into lump-sum tools
- Confusing ROI and CAGR
Quick tool map
- ROI snapshot: ROI / PnL Calculator
- Time-normalized comparison: CAGR Calculator
- Planning with contributions: Compound Interest Calculator