Compound Interest Calculator with Monthly Contributions
See how your money can grow over time. The power of compound interest means your interest earns interest.
Future Value
Growth Schedule
| Year | Total Invested | Interest | Total Balance |
|---|---|---|---|
| Year 1 | $11,000 | $558 | $11,558 |
| Year 2 | $17,000 | $1,590 | $18,590 |
| Year 3 | $23,000 | $3,130 | $26,130 |
| Year 4 | $29,000 | $5,215 | $34,215 |
| Year 5 | $35,000 | $7,885 | $42,885 |
| Year 10 | $65,000 | $31,591 | $96,591 |
How much could monthly contributions grow over time?
Enter a starting deposit, monthly contribution, assumed annual return, and number of years. This projection compounds monthly and adds contributions at month end. Compare contributions with interest in the yearly breakdown; actual investment returns will vary.
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How to use this calculator
The Eighth Wonder of the World
Albert Einstein famously called compound interest the "eighth wonder of the world," stating, "He who understands it, earns it... he who doesn't... pays it." Compound interest is the process where the interest you earn on your money starts earning interest itself. Over time, this snowball effect can turn modest monthly savings into a substantial nest egg.
Our **Compound Interest Calculator** helps you visualize this powerful force. By inputting your initial investment, monthly contributions, interest rate, and time horizon, you can see exactly how your money will grow exponentially.
Key Variables Driving Growth
Time
Time is your greatest asset. The longer your money stays invested, the more it compounds. Starting 10 years earlier can double or triple your final outcome with the same monthly contribution.
Interest Rate
The rate of return determines how fast your money grows. While savings accounts offer 0.5% to 4%, stock market index funds have historically returned around 10% annually over long periods (before inflation).
Compounding Frequency
How often is interest added to the principal? Daily compounding grows wealth faster than monthly or annual compounding because the interest has more opportunities to earn more interest.
Regular Contributions
Adding a fixed amount monthly (Dollar Cost Averaging) accelerates growth significantly and smooths out market volatility risk over time.