Investment Growth Calculator
See how your investments grow with compound interest over time. Enter your starting amount, regular contributions, and expected return rate to project your portfolio's future value.
Starting with $10,000 and adding $500 per month at a 10% annual return for 20 years, you'd contribute a total of $130,000 — and your investment would grow to approximately $452,965 thanks to compound interest. That's $322,965 in pure growth.
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Your projected investment growthEnter your investment parameters and click calculate to see projected growth.
Frequently Asked Questions
Key concepts for long-term wealth building
How does compound interest work?
Compound interest means you earn returns not just on your original investment, but also on all the returns that have already accumulated. In year one, $10,000 at 10% earns $1,000. In year two, you earn 10% on $11,000 — that's $1,100. Each year, the growth accelerates.
Albert Einstein reportedly called compound interest 'the eighth wonder of the world.' The key factor is time — $10,000 growing at 10% becomes $67,275 after 20 years and $174,494 after 30 years. Starting just 10 years earlier nearly triples your money.
How much difference do regular contributions make?
Regular contributions dramatically amplify compound interest. A one-time $10,000 investment at 10% grows to $67,275 in 20 years. But adding just $200 per month to that same investment turns it into $210,037 — more than three times as much.
The key is consistency. Even small monthly contributions create a powerful snowball effect because each deposit starts compounding immediately. A $200 monthly contribution over 30 years at 10% turns $72,000 in deposits into over $450,000 — that's the difference between saving and investing.
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All calculations run entirely in your browser. We never collect, store, or transmit any data you enter into this calculator. There are no APIs, no server requests, and no logs — your financial information stays on your device and disappears when you close the page.