What is compound interest?

Compound interest is interest that is earned not only on the original principal, but also on the accumulated interest of previous periods.

To calculate compound interest, one must first determine the periodic interest rate—the interest rate charged for one time period. The periodic rate is expressed as a percentage of the principal. The total amount of interest paid over the life of a loan is greater with compound interest than with simple interest.

Compound interest is often called the eighth wonder of the world. It is the most powerful force in the universe. Albert Einstein is quoted as saying, Compound interest is the eighth wonder of the world. He who understands it, earns it ... he who doesn't ... pays it.

How is compound interest calculated?

The basic formula for compound interest is:

A = P(1 + r/n)nt


  • A = the future value of the investment/loan, including interest
  • P = the present value of the investment/loan
  • r = the annual interest rate (decimal)
  • n = the number of times that interest is compounded per year
  • t = the number of years the money is invested or borrowed for

What are the benefits of compound interest?

Compound interest has the effect of snowballing. The more money you have invested, the more money you will earn in interest. This can lead to a significant increase in wealth over time.

Compound interest is also a powerful tool for wealth building. When you reinvest your interest payments, you are effectively compounding your returns. This can help you to build wealth more quickly than if you simply saved your money.

What are the drawbacks of compound interest?

Compound interest can work against you if you have debt. This is because you will be paying interest on the interest that you have already accrued. This can lead to a spiral of debt that can be difficult to break out of.

How can I make the most of compound interest?

To make the most of compound interest, you should:

  • Invest early and often: The sooner you start investing, the longer your money will have to grow.
  • Reinvest your interest payments: This will help you to compound your returns and build wealth more quickly.
  • Choose a high-interest investment: This will help you to earn more money in interest.
  • Be patient: Compound interest takes time to work its magic. The longer you invest, the more you will benefit from it.

Is compound interest right for me?

Compound interest can be a powerful tool for wealth building. However, it is not right for everyone. You should carefully consider your investment goals and risk tolerance before deciding whether or not to invest in a compound interest account.

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