What is compound interest, and why bother with it? It might seem irrational to invest a single dollar right now, yet that simple investment with compound interest can be incredibly effective; that lone dollar that was put in could then be worth much more.

Choosing a significant, more hazardous decision without hesitation could be alluring, but compound interest is quite possibly the most effective resource for your investment plans. Albert Einstein referred to it as being the greatest act of ingenuity in the history of humankind. So why do so few of us take advantage? Many people fail to make an effort to grasp the notion completely.

But you’re not one of those people. You desire to have an exhaustive knowledge of the interpretation of compounded interest and how it functions so that you can consciously save. Compounding interest can assist in advancing one’s fiscal independence, even if it is just a dollar at once. This type of investment strategy can be beneficial by taking advantage of the passing of time.

**Compound interest definition**

What is compound interest? Let’s start with a dictionary compound interest definition to establish the core meaning of the term:

Compound Interest is a type of calculation used to determine the interest owed on the original principal loan and any subsequent interest added.

In other words, compound interest is interest on interest. When you put the interest earned back into the investment instead of withdrawing it as income, this implies that interest during the following period is made not just on the original amount but also on the interest accumulated over time. Your earnings are determined by the amount of money you have put in, the interest rate given on that quantity, and the number of compounding periods per annum. The amount of times compounding can occur varies, with options including annual, semi-annual, quarterly, monthly, weekly, daily, or ongoing. The more often your interest is recalculated and added to your total, the more interest you will gain.

Let’s use a numerical example to gain a better understanding of what compound interest is. After one year, you would have accumulated an additional three dollars with your initial hundred-dollar investment if the annual compound interest rate was 3%. For year two, interest is earned on all $103, thus you get $3.09 in interest for that year as opposed to a uniform $3.00. For in the third year, you will gather interest from a sum of one hundred and six dollars and nine cents, and in turn, it will accumulate in the same manner. If you invested $100 over twenty years, you would have a total of $180.61 by the end. This is due to gaining a 3% interest rate annually.

**Simple interest vs. compound interest**

Interest that is yielded only on the original amount invested is referred to as simple interest. As an illustration, if you had $100 and an annual interest rate of 3%, you would collect $3 annually. The amount of money you would make in interest will stay the same throughout the years due to the fact that the original amount does not alter. For example, you would generate $3 each year, so after 20 years you will have $160 (the initial $100 plus $3 multiplied by 20).

In reference to the illustration provided, compound interest offers an additional $20 in comparison to regular interest over the same length of time. This might not appear to be signed immediately, but it could accumulate with the passage of time.

It is important to understand the distinction between the Annual Percentage Rate (APR) and the Annual Percentage Yield (APY). Annual Percentage Rate, or APR, is the yearly interest rate on a loan that does not consider compounding. APY stands for annual percentage yield. This is a rate that shows the entire amount of interest charged to the account. This is calculated using the interest rate compounded every day during a year-long time frame. The rate of compound interest is noted on certain types of investments.

**The compound interest formula**

In order to get a thorough understanding of what the expression “compound interest” implies, let us analyze the formula. It may appear to be complex initially, but it is quite straightforward in reality. The equation is expressed as A = P (1 + r/n) (nt). Input the original principal into the P box, type the interest rate as a decimal into the r space, fill out the n section with the number of times the interest is compounded, and type the investment period in the (nt) spot.

If you put $5,000 into a savings account with a yearly rate of 5%, compounded each month, this is how it would look: 5000 (1 + 0.05/12) raised to the 12th power, meaning it would equal 8235.05. Your financial expenditure of $5,000 has appreciated to more than $8,000 in a decade.

**What is compound interest? Examples with numbers**

Investing your hard-earned money is always a big decision. To make that decision easier, let’s take a look at some investment scenarios that can help you better understand how your money can grow over time.

1) Let’s say you invest $10,000 for a period of five years, with a 3% return that is compounded monthly. At the end of the five-year term, your initial investment of $10,000 has grown to a substantial $11,616.17. Imagine the possibilities of what you could do with that extra money!

2) If you have a shorter investment horizon of two years, and invest the same $10,000 with a 2% return that is compounded quarterly, you will still be able to see growth. At the end of the two-year term, your initial investment will have grown to $10,404.07. That’s still a decent return for a shorter period of time.

3)For those who may not have as much to invest, let’s consider an initial investment of $1,000 for a year with a 5% return that is compounded twice a year. At the end of the year, your initial investment of $1,000 has grown to $1,050.63. That may not seem like much, but every little bit helps.

Investing your money can help you grow your wealth over time, but it’s important to keep in mind that all investments come with risks. It’s important to do your research and seek professional advice before making any investment decisions.

Burton Malkiel, a financial expert, proposed the concept of index funds. He shared a fantastic tale of two siblings investing which is an excellent illustration of how to generate a steady income.

Take two brothers, we’ll call them William and James. Both are 65 years old. Which brother will have more money in their account at retirement, based on the given data? Which of the two, William or James, has invested for a longer period of time, 20 or 25 years? Click below to find out.

William made six times as much money as his brother despite investing the same amount for a shorter period. The picture here demonstrates accurately why compound interest is such a crucial part of the vocabulary of the affluent. Even if you’re past your twenties, you can still leverage the power of compounding interest by contributing whatever amount you can at the present time. If you delay, you will miss out on additional income.

**The Power of Compound Interest**

Compound interest builds on itself due to the fact that it accumulates interest from previous intervals, leading to a steadily faster rate of increase. Over the course of the three years of the loan, the total interest paid amounts to $1,576.25; however, this is not constant throughout, as it would be with traditional interest calculations. The table below illustrates how much interest is due to be paid every year.

Investments made with compound interest can show greatly magnified yields over a long period of time. If you put $100,000 into a bank account with a 5% simple annual interest rate, you would make $50,000 in interest after 10 years. Alternatively, if you invest $10,000 at the same 5% compound annual interest rate, you would accrue $62,889.46 in interest after a decade. If the same 10-year period at 5% compound interest were calculated on a monthly basis, the interest earned would be $64,700.95.

**Compound Interest Schedules**

The interest earned can be accumulated over any length of time, ranging from every day to once a year. In the financial world, there is usually a set routine in which instruments are compounded.

Regular banking practice involves the daily accumulation of interest on savings accounts. For a certificate of deposit, commonly the interest earned is counted on a daily, monthly, or semi-annually basis, while in the case of money market accounts, it is usually done on a daily basis. The most typical way of calculating interest for home loans, home equity loans, personal business loans, and credit card accounts is to add it on a monthly basis.

The amount of time in which interest accumulates can fluctuate, and it will be applied to your current balance. The interest accrued in an account may be calculated on a daily basis yet only added to the balance on a month-to-month basis. The additional interest will only be earned when the interest is taken into consideration and added to what’s already present in the account.

Certain banks provide something named perpetually compounding interest, which adds interest onto the base amount at any feasible time. For practical applications, it doesn’t make that much of a difference if you regularly compound interest except if you plan to deposit and withdraw money on the same day.

Interest accrual at a more frequent rate is advantageous for the investor or lender. For a borrower, the opposite is true.

**Compounding Periods**

When figuring out compound interest, the amount of time when the interest is being added has a major effect. The more often the money is compounded, the larger the amount of compound interest earned.

The table below shows how a 10-year $10,000 loan with an annual 10% interest rate can be affected by the number of periods it is compounded.

**Compound Interest: Start Saving Early**

Young people often neglect to save for retirement. Individuals in their twenties often find that the future seems like it is a long way off, making more pressing expenses appear to be of greater importance. It is during these years that compound interest can be a drastic alteration: Putting away a small amount today can reap immense rewards for the future – much more than stashing away more money in later years. Here’s one example of its effect.

If you begin putting money into the stock market on a monthly basis in your twenties starting with $100. Let’s suppose that you gain a return of around 1% each month (which is equivalent to 12% a year), which is accumulated monthly over a span of 40 years. Let us envision that your identical sibling, who is the same age, holds up until the age of 30 before investing. Your late brother or sister puts away $1,000 each month for a 10-year period, gaining the same level of increase in value over the course of the investment.

At the 40-year milestone, your twin will have accrued around $230,000 in savings while you will have amassed more than $1.17 million. Even though your twin invested more than you over the course of time, the power of compounding resulted in your portfolio being larger by a factor of more than five.

It would make sense to consider opening a personal retirement account (IRA) and/or capitalizing on a retirement plan supported by an employer, such as a 401(k) or 403(b) program. Begin to save in your twenties and make sure to pay into the account regularly. You’ll be glad you did.

**Pros and Cons of Compounding**

Though Albert Einstein supposedly hailed compounding as the eighth wonder of the world or man’s best invention, it can also be detrimental to individuals with loans that feature staggeringly high-interest rates, for example, credit card debt. A credit card balance of $20,000 with an interest rate of 20% compounded monthly would lead to a total compound interest of $4,388 after 12 months, equalling approximately $365 per month.

Compounding can be beneficial when it comes to your investments and can be a contributing factor to an increase in your wealth. The ability to compound interest to produce exponential growth is crucial in helping to counterbalance factors that can diminish wealth, for instance, the rising cost of living, inflation, and reduced spending power.

Mutual funds present a straightforward method for investors to take advantage of compound interest. Choosing to put dividends gained from the mutual fund back into it will result in buying additional shares of the fund. Compounding interest will continue to build up over the course of time, and the ongoing process of buying more shares will help the investors in the fund increase in value.

Think about investing in a mutual fund with an initial deposit of $5,000 and a subsequent yearly contribution of $2,400. Over a 30-year period, the fund has had an annual average of 12% return, resulting in its current value of $798,500. Compound interest is the increase in the investment value due to the addition of income generated from the original principal amount. In this scenario, by making a total contribution of $200 per month for 30 years, compounded interest will bring the future balance to $721,500. The sum of the initial contributions will be $77,000.

Compound interest earnings must be taxed unless the funds are in an account that is protected from taxation. Typically, the income from this portfolio is subject to prevailing tax rates determined by your income level, and if the investments don’t pan out, your bottom line could suffer.

Kurt has gone from the financial lows of the ’08 financial crisis to personal financial success. He is a professional real estate investor, media buyer, faithful Red Sox Fan.

One of his passions is financial education and the pursuit of financial freedom.

You can learn more about Kurt here, or get a hold of him on Facebook or Twitter.