Investment Calculator
Quickly find your Investment growth with our free Investment Calculator. Simple, fast, and accurate.
Your investment
Future value
What is an Investment Calculator?
An Investment Calculator projects how your money could grow over time. Enter your starting amount, annual contribution, expected return rate, and investment period to see the future value of your investments and how much of that growth comes from compounding.
How to calculate investment growth manually (the formula)
The future value formula is: FV = PV × (1 + r)t + C × [ (1 + r)t – 1 ] / r where PV is the starting amount, C is the annual contribution, r is the expected annual return, and t is the number of years.
Example calculation
If you invest $10,000 today and add $3,000 per year at a 7% annual return for 20 years: the future value would be about $161,500. You contributed $70,000 of your own money, and the remaining $91,500 is investment growth.
Common mistakes
- Overestimating expected returns — Using a very high return rate leads to unrealistic projections. A 5–8% rate is typical for long-term planning.
- Not accounting for inflation — Inflation reduces real purchasing power. If you expect 7% nominal returns, the real return after 3% inflation is about 4%.
- Stopping contributions too early — Consistent contributions matter more than timing the market. Even during downturns, continuing to invest allows you to buy at lower prices.
- Ignoring fees and taxes — Management fees, expense ratios, and taxes can significantly reduce net returns. Look for low-cost index funds and tax-advantaged accounts.
- Trying to time the market — Even professional investors struggle to time the market. A consistent buy-and-hold strategy typically outperforms frequent trading.
Frequently asked questions
How does an investment calculator work?
An investment calculator projects the future value of your investments based on your starting amount, annual contributions, expected return rate, and investment period. It uses compound growth math to estimate your returns.
What is a good rate of return on investments?
Historically, the stock market averages 7–10% annual returns before inflation. For conservative planning, 5–7% after inflation is often used. Past performance does not guarantee future results.
How does compounding affect investment growth?
Compounding means you earn returns on both your original investment and on previously earned returns. Over long periods, this creates exponential growth — the earlier you start, the more powerful the effect.
What is the difference between simple and compound interest?
Simple interest is calculated only on the principal. Compound interest is calculated on the principal plus accumulated interest, leading to faster growth over time. Most investment growth comes from compounding.
Is this calculator free to use?
Yes, completely free with no sign-up or download required. You can use it as many times as you like.