FTF Finance / Saving & Investing
Compound interest calculator
Explore how a starting balance and regular contributions could grow over time. Change the assumptions to compare different scenarios.
Your scenario
Results update as you change the inputs.
Changes the denomination, not the exchange value. Numbers use commas for grouping and a decimal point.
Zero or greater. Maximum USD 100,000,000.00.
Added at month-end. Maximum USD 1,000,000.00.
Enter 6 for 6%. Allowed range: 0%–30%.
Enter a whole number from 1 to 50.
Projected results
Estimated balance after 10 years
USD 18,207.33
Total contributed
USD 13,000.00
Estimated interest
USD 5,207.33
What makes up the balance?
Fixed nominal annual rate, compounded monthly. Contributions are added at month-end. Taxes, fees, inflation, and exchange-rate changes are excluded. Displayed amounts are rounded; calculations are not rounded each month.
Year-by-year breakdown
Cumulative amounts in USD.
| Year | Contributed | Interest | Balance |
|---|---|---|---|
| 1 | USD 2,200.00 | USD 95.23 | USD 2,295.23 |
| 2 | USD 3,400.00 | USD 270.36 | USD 3,670.36 |
| 3 | USD 4,600.00 | USD 530.29 | USD 5,130.29 |
| 4 | USD 5,800.00 | USD 880.27 | USD 6,680.27 |
| 5 | USD 7,000.00 | USD 1,325.85 | USD 8,325.85 |
| 6 | USD 8,200.00 | USD 1,872.93 | USD 10,072.93 |
| 7 | USD 9,400.00 | USD 2,527.76 | USD 11,927.76 |
| 8 | USD 10,600.00 | USD 3,297.00 | USD 13,897.00 |
| 9 | USD 11,800.00 | USD 4,187.69 | USD 15,987.69 |
| 10 | USD 13,000.00 | USD 5,207.33 | USD 18,207.33 |
How this estimate works
Interest is compounded monthly. The annual rate you enter is a nominal annual rate, divided by 12 to calculate the monthly rate. It is not an APY input.
Each month, interest is applied to the existing balance, then your monthly contribution is added. Contributions therefore occur at the end of each month.
Next balance = current balance × (1 + annual rate / 12) + monthly contribution
In this formula, the annual rate is expressed as a decimal: 6% becomes 0.06. Calculations retain full precision; displayed amounts are rounded to cents.
This illustration assumes a constant rate and excludes taxes, fees, inflation, and withdrawals. Actual investment returns fluctuate and can be negative. Results are not guaranteed and are not personalized financial advice.