Finance calculator

Compound Interest Calculator

Explore how time, contributions, and return assumptions combine to grow long-term savings.

Deterministic math. No account required.

Your details

Your results

Future value$63,368
Total contributions$40,000
Estimated growth$23,368

Projected balance

Contributions $40,000 Growth $23,368
Projected future value$63,368
10-year projection

How the compound interest calculator works

Project investment growth with compound returns and regular monthly contributions.

Formula

Future value combines compound growth on the initial balance with the future value of recurring contributions.

Example

$10,000 invested for 10 years at 7%, plus $250 each month, grows through both contributions and compounded returns.

What affects the result

  • More time allows returns to compound over more periods.
  • Regular contributions can matter as much as the starting balance.
  • Actual market returns vary and are not guaranteed.

Helpful guides

Frequently asked questions

What does compounding mean?

Compounding means earning returns on both your original money and prior returns.

Is the result guaranteed?

No. It is a mathematical projection based on a constant rate, not a prediction of investment performance.

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