Compound Interest Calculator

See how your money can grow over time. Enter your starting amount, monthly contributions, and expected return rate.

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Results

Final Balance

Total Contributions

Total Interest Earned

Contributions (%) Interest (%)

Year-by-Year Breakdown

Year Contributions Interest Balance

What is compound interest?

Compound interest is when you earn interest not just on your original investment, but also on the interest you've already earned. It's often called "interest on interest" and is one of the most powerful forces in personal finance.

The key to compound interest is time. The longer your money compounds, the faster it grows. Even small monthly contributions can turn into significant wealth over decades. This is why starting early, even with small amounts, matters so much.

Use the calculator above to see how different contribution amounts and time periods affect your final balance. Try adjusting the monthly contribution to see the dramatic difference even $50 more per month can make.

Put your plan into action

Start budgeting with Hearth and watch your savings grow.