See how your money grows with compound interest over time.
Contributions vs interest earned over time
This investment calculator shows how your money grows through the power of compound interest. Enter your initial investment, monthly contribution, expected annual return, and time horizon to see your projected final balance. The year-by-year growth chart visually separates your contributions from investment gains, making it easy to see how compounding accelerates your wealth over time.
Choose between monthly, quarterly, or annual compounding to match your actual investment product. Monthly compounding produces slightly higher returns because interest starts earning its own interest sooner. Over a 20-year period, this difference can add up to a meaningful amount, especially with larger portfolios or higher return rates.
The most powerful variable in this calculator is time. Even modest monthly contributions grow substantially over decades thanks to compounding. Try extending the time slider to see how an extra five or ten years dramatically increases your final balance. Starting early, even with smaller amounts, often beats starting late with larger contributions.
Planning specifically for retirement? Our retirement calculator factors in inflation and the 4% withdrawal rule. To understand how your current income fits into your savings plan, try the salary calculator.
Plan your long-term wealth with the retirement calculator, measure returns on any venture using the ROI calculator, or compare financing costs with our mortgage calculator.