Compound Interest Calculator

Calculate how your investments grow over time with compound interest

Results:

$0.00 Future Value
$0.00 Total Principal
$0.00 Total Interest

About Compound Interest Calculator

The compound interest calculator helps you estimate how your investments will grow over time with the power of compounding. Whether you're planning for retirement, saving for a major purchase, or just curious about investment growth, this calculator provides a clear picture of your potential financial future.

What is Compound Interest?

Compound interest is the addition of interest to the principal sum of a loan or deposit, or in other words, interest on interest. It is the result of reinvesting interest, rather than paying it out, so that interest in the next period is earned on the principal sum plus previously accumulated interest.

How to Use the Compound Interest Calculator

  1. Enter your Initial Investment amount (principal).
  2. Specify the Annual Interest Rate as a percentage.
  3. Set the Time Period in years for your investment.
  4. Choose the Compounding Frequency (how often interest is calculated).
  5. Add any Regular Contribution you plan to make.
  6. Select your Contribution Frequency.
  7. Click the "Calculate" button to see your results.

Understanding the Results

  • Future Value: The total value of your investment after the specified time period.
  • Total Principal: The sum of your initial investment and all additional contributions.
  • Total Interest: The amount earned from interest over the investment period.

The Compound Interest Formula

The formula used to calculate compound interest with regular contributions is:

A = P(1 + r/n)nt + PMT × [(1 + r/n)nt - 1] / (r/n)

Where:

  • A = Final amount
  • P = Principal (initial investment)
  • r = Annual interest rate (as a decimal)
  • n = Number of times interest is compounded per year
  • t = Time in years
  • PMT = Regular contribution amount

The Power of Compound Interest

Compound interest is often called the "eighth wonder of the world" because of its remarkable ability to grow money over time. The longer the time period, the more dramatic the effect becomes. This is why starting to save and invest early is one of the most powerful financial strategies.

Tips for Maximizing Compound Interest

  • Start early: The sooner you begin saving, the more time your money has to grow.
  • Be consistent: Regular contributions, even small ones, can significantly increase your end result.
  • Reinvest dividends: When possible, reinvest any earnings to take full advantage of compounding.
  • Consider higher compounding frequencies: More frequent compounding leads to higher returns over time.
  • Be patient: The true power of compound interest becomes evident over longer time periods.