Investment Calculator

Plan your financial future with our investment calculator. Estimate how your investments could grow over time with compound interest and regular contributions.

Investment Growth Calculator

$

Your starting investment amount.

$

Amount you plan to add every month.

%

Expected yearly return on investment (before fees).

How long you plan to keep your money invested.

How often interest is calculated and added to your investment.

%

Annual management and service fees (percentage).

%

Expected annual inflation rate for calculating real value.

How Investment Growth Works

Investment growth is primarily driven by compound interest — when you earn interest not only on your principal, but also on the interest you've already accumulated. This creates a snowball effect that accelerates your wealth building over time.

Regular contributions amplify this effect, adding fresh capital that also starts earning compound returns. The longer your money remains invested, the more powerful this compounding effect becomes.

The Compound Interest Formula

The mathematical formula that powers investment growth calculations is:

$$A = P(1 + r/n)^(nt) + PMT * ((1 + r/n)^(nt) - 1) / (r/n)$$

Where: A = final amount, P = principal, r = annual interest rate, n = compounding frequency, t = time in years, PMT = regular payment amount.

Key Factors Affecting Your Investment Returns

Time Horizon

The length of time you keep your money invested is perhaps the most important factor. Compound interest works exponentially, so longer investment periods see dramatically higher returns.

Rate of Return

Higher return rates lead to substantially larger growth over time. However, investments with higher potential returns typically come with higher risk and volatility.

Regular Contributions

Consistently adding to your investments significantly increases your final value. Even small regular contributions can have an enormous impact over long periods.

Investment Fees

Fees can dramatically reduce your long-term returns due to their compounding effect. Even a 1% difference in annual fees can reduce your final balance by 20% or more over several decades.

Investment Strategies to Maximize Growth

  • Start early: Even small amounts invested in your 20s can outperform larger amounts invested in your 40s due to compound interest.
  • Invest regularly: Set up automatic contributions to maintain discipline and take advantage of dollar-cost averaging.
  • Minimize fees: Choose low-cost index funds or ETFs when possible to reduce the drag of fees on your returns.
  • Diversify appropriately: Balance risk and return based on your time horizon and risk tolerance.
  • Reinvest dividends: Allow your earnings to generate more earnings by reinvesting rather than withdrawing.

How to Use This Investment Calculator

  1. Enter your initial investment amount — this is the money you're starting with.
  2. Specify any regular contributions you plan to make, such as monthly additions to your investment.
  3. Enter your expected annual rate of return, investment time period, and any applicable fees or inflation expectations.
  4. Click 'Calculate' to see detailed projections of your investment growth over time.

Use these projections to set realistic financial goals, compare different investment strategies, and understand the impact of various factors on your long-term returns.