Finance

Compound Interest with Contributions Calculator

Project growth when you add a regular contribution on top of a starting amount.

The result shows the final value, the total amount put in, and the interest earned, so the gap between the final value and the total contributed is the growth from compounding over time.

Formula

Final value is the growth of the starting amount plus the future value of monthly contributions at the monthly rate.

How it works

Regular contributions often matter more than the starting amount over long periods. This assumes deposits at the end of each month and a steady rate.

Worked example

For example, a starting amount of $5,000 with $300 contributed each month at a 7% annual interest rate for 20 years gives a final value of $176,471.69, total contributed of $77,000.00, and interest earned of $99,471.69.

FAQs

How do contributions change the result?
They add principal every month, and each deposit then compounds too.

What if I increase contributions later?
Run the calculator again with the higher amount for the remaining years.

Are taxes included?
No, this is a before-tax projection.

Are these figures financial advice?
No — they are estimates for planning only, not financial advice. Check with a qualified adviser for decisions involving large sums.

Estimates only, not financial advice. Figures are approximate and do not include all fees, taxes, or changing rates unless stated.

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