Investment Calculator

What is investment calculator?

An investment calculator projects how your savings will grow over time using compound interest. You enter your starting balance, how much you plan to add each month, an estimated annual return rate, and the number of years to invest. The calculator then separates your total into two parts: the future value of your initial lump sum, and the future value of your ongoing contributions — so you can see exactly how much came from each source. This tool is valuable for long-term planning: retirement, college savings, or any goal where time and compounding do the heavy lifting. Try adjusting the monthly contribution up or down, or running the same scenario at different return rates (e.g. 5% conservative versus 9% optimistic), to see the range of possible outcomes. No account numbers or personal data are needed — everything runs in your browser.

How to use this calculator

1. Enter your initial investment.
2. Enter your monthly contribution.
3. Enter your estimated annual return.
4. Enter your years to grow.
5. Click the "Calculate" button.
6. View your result instantly — the main result is displayed prominently at the top with a detailed breakdown below it.

When to use this calculator

• Projecting retirement savings growth over 20, 30, or 40 years
• Comparing the impact of different monthly contribution amounts
• Seeing how starting early (more years) dramatically increases final wealth
• Running conservative (5%) vs. optimistic (9%) return scenarios
• Estimating how much you need to save monthly to reach a target number