Worked example
At 5% nominal interest compounded monthly for 10 years, $5,000 grows to around $8,235.
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Loans & savings
Compound Interest Calculator
Estimate how a starting balance grows with periodic compounding.
Enter your numbers
Adjust the example to calculate using your own figures. Results update instantly.
Your results
Calculated locally- Future balance
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- Interest earned
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How compound interest grows over time
Compare the starting amount with estimated future balances at selected milestones. Unlike a savings plan with recurring deposits, this table follows one balance with no additional contributions.
| Year | Balance | Interest earned |
|---|---|---|
| 0 | $5,000.00 | $0.00 |
| 1 | $5,255.81 | $255.81 |
| 2 | $5,524.71 | $524.71 |
| 3 | $5,807.36 | $807.36 |
| 5 | $6,416.79 | $1,416.79 |
| 10 | $8,235.05 | $3,235.05 |
Illustrative compounding at the constant rate you enter; not an investment return forecast.
Important assumptions
Assumes constant nominal rate and no deposits, withdrawals, taxes or investment losses.
How to use your results
Interest accumulates on both the original amount and previous interest. At a fixed nominal rate, the compounding frequency affects the total.
Start with the example values, then replace them with amounts for the same transaction or time period. Double-check rates and units. The results are estimates intended to help you explore possible outcomes, not financial or tax advice.
Compounding frequency changes the outcome
At the same nominal annual rate, interest credited monthly has more chances to earn additional interest than interest credited once a year. The difference may be modest over a short period and more meaningful over longer horizons.
A projection is not a guaranteed return
Bank deposits may have fixed stated interest for a period, while investments can fluctuate and lose principal. Do not treat a constant positive compound-interest line as a forecast of market prices. Compare realistic rates and account for tax and fees.
Does this tool include contributions every month?
No. It grows one initial balance without extra deposits. To work toward a savings target with recurring deposits, use our Savings Goal Calculator.
How to calculate compound interest
Future value = P × (1 + annual rate ÷ n)^(n × years)
Interest accumulates on both the original amount and previous interest. At a fixed nominal rate, the compounding frequency affects the total.