Compound Interest Calculator

What is Compound Interest?

It is hard to say if anyone knows the exact day when compound interest was invented, but we know that it existed in ancient Babylon and in medieval times. This interest was called interest on interest in ancient times, and that perfectly reflects its essence.

Compound interest is a type of interest that allows you to increase your savings faster than regular interest. It is calculated on the principal amount and any accumulated interest from previous periods. This is similar to the automatic reinvestment of income regarding deposits. Therefore, it is essential to know when you start saving, even from a simple step, the decision to open a savings account in the bank.

In other words: the money you earn earns you more, and you get higher returns. Compared to regular interest, you can double your investment faster.

Compound interest can be used for deposits stored on savings accounts and loans. The algorithm is the same in both cases: the capital constantly grows by adding the accrued interest from previous periods. The rate of capital growth depends on:

• how high the interest rates are;

• interest accrual compounding interval;

• the amount of principal.

Such growth is often referred to as a compound interest miracle, and this miracle can be predicted with a compound interest formula.

Once you know the formula, you can calculate compound interest for your case.

1. The initial principal amount is multiplied by one plus the annual interest, which is raised to the number of compound interest periods minus one.

2. The initial total amount of the loan is subtracted from the value obtained in step one.

As customers or investors, we need compound interest to understand the principle of how financial instruments work and which amount of money they earn. It is always good to get an idea of what we are using to get the most benefit from the instrument or to choose the wisest alternative. For example, if you decide to invest money and know the essence of compound interest, you would probably prefer that product rather than a simple interest product. If you want to take out a loan, you need to know how the interest is calculated and what the costs are. When you learn that if you default, interest will be added to the principal balance, and other interest will be added, you can plan to pay the installment accurately enough so that you do not overpay for the loan.

As we showed in the previous example, compound interest is needed to reach your future value goals faster. Depending on your experience in the market, you should choose the appropriate instruments and build a mix of low, medium, and high-risk instruments. The same is true for loans. If you need this instrument, you should weigh your risks wisely and remember that you are paying for the service of temporary access to the lender's money from your income.

Compound interest works on your wealth if it is related to your investments, deposits, etc. But sometimes, our financial issues include loans, and that's where we have to be careful that compound interest does not become an anticlimax that rips our finances out of our budgets. Credit cards, for example, have high-interest rates and are expensive instruments. So when high-interest rates are added to your negative balance each month, it can become a financial trap with an unpleasant outcome.

Take time to review the terms of the financial alternatives and products offered to you and, if possible, use compound interest on your team to grow your wealth rather than increase your liabilities.

Simple Interest vs. Compound Interest

As you may know, there are two types of interest: simple and compound. Both have advantages and some side effects. It depends on where the interest is applied.

Simple interest is based on your original principal amount. It does not matter if it is a deposit or a loan. Simple interest refers to the most standard crediting type.

Compound interest itself can also be applied to both investments and loans. Its calculation is based on the principal and the number of compound interest periods.

Both compound interest formulas can be applied manually or with the help of apps or calculators, and it is essential to know the formula and enter the data accurately. However, it is generally considered that simple interest rates are easier to calculate.

When it comes to investments, they grow slower if you use the simple interest program. Of course, you can manually "top up" your deposit if the product allows you to top up the interest amount on your instruction regularly, but some products do not offer this option. You'll have to find out for yourself.

Compound interest allows your money to work more efficiently for you because the capital on your investment account, including the interest earnings, works for you without spending any additional money.

From an investing standpoint, compound interest is more than a friendly tool for building your wealth. But if you are a borrower and interest is your cost of borrowed money, compound interest creates a higher cost. It all depends on the product terms. For example, if you pay the interest without delay, the interest will not be added to the principal without creating a credit trap. However, if you default, the interest may be added to the principal, and you will have to pay more.

Why do we need a compound interest calculator?

Compound interest is not as complicated as you might imagine. You can calculate compound interest even if you have not taken any special courses on finance, banking, etc.

Compound interest can be calculated in a way that is convenient for you:

• manually;

• with Excel;

• Google Sheets;

• with the help of a battery calculator;

• using an online compound interest calculator, etc.

The choice depends on your preferences, time, and convenience.

To calculate compound interest, you need to calculate the annual capitalization (if income is compounded annually). Then add the interest for the first year to the principal (if it is a long-term deal, over one year). The same calculation should be done on paper or a calculator annually when you need the picture for each year. Yearly, monthly, or other periods should be used as long as the future tendencies of the market are unclear.

Remember, compound interest is calculated by multiplying the initial principal amount by one plus the annual interest rate, which is raised to the number of compounding periods minus one. It can be used to find out total deposit earnings, etc.

You can use your notebook to calculate or enter your data into Excel. If you are uncomfortable with the compound interest formula, you can also use an online calculator. It can be any calculator, but the compound interest calculator allows you to spend the least effort and still get accurate results.

The calculator usually requires you to enter information in this form:

• Total amount (the amount you invest initially);

• Number of years to accumulate (income in case you pay in);

• Contribution amount and periods for regular contributions;

• (expected) return on the investment;

• compounded interest;

• Compounding intervals (compounded daily, monthly, bi-weekly, semi-annually, etc.). In less than half a minute, you will get the result of your projected interest earned or hypothetic loan expenses during the compounding period.
  With the online compound interest calculator, you do not need to install an app; you just need to access the Internet and charge the battery if you use a netbook, Android, iOS, etc.

How to Calculate Compound Interest

You can use different calculation tools for compound interest depending on your preferences. The main thing is to be up to date on the state of your finances and get a clear picture with accurate figures. Let us start our overview with the manual calculation option.

Once you know the formula, you can calculate compound interest for your case. See below one of the compound interest formulas. Compound interest calculations can be performed using certain formulas, for example, this one:

A=P(1+r/n)^nt where:

• A means the accrued amount (principal amount and interest amount);

• P stands for principal amount;

• r means the decimal form of the annual interest rate.

• R denotes the annual interest rate in percent r=R/100;

• n stands for the number of compounding periods;

• t denotes the number of years, decimal (12 months = one year, six months = 0.5 years time period, etc.) decimal years are calculated by dividing by 12

• I = interest amount.

In Excel, the method of calculation depends on whether you create a table with your initial data and then also calculate parts, which you combine with the final calculation to get the result; or whether you create a formula that takes your initial data from the table and gives you the result in one step. Using a formula saves you time because you can change rates, compounding periods, the initial principle, etc., and see different results.

Using formulas in Excel is similar to another handy tool: the online compound interest rate calculator. You just need to enter the website and your data, and you will get your results with one click.

To perform compound interest calculation, you can use any calculator; if it is at least a scientific calculator that offers the possibility to raise to a specific power, etc., it is much more convenient to find out the total interest and cost.

Compound interest on a loan

When applying for a loan, you need to check several details specified by financial institutions. Not least, you need to understand how interest is paid over time and how it is calculated. However, it is not enough to just know the interest rate. Below we explain why.

There are different types of interest, including fixed-rate, annual rate, floating, and compound rate (the letter can be even daily interest rate). Floating interest can sometimes be advantageous. On the one hand, a fixed interest rate is beneficial because it does not change over time, but sometimes market conditions change for the better. Still, you cannot take advantage of that opportunity unless you obtain refinancing at a better rate.

The compound interest rate benefits lenders because it earns more money for the lending institution.

Mortgages, student loans, credit cards, and many other loans may have compound interest. Therefore, one should carefully read the terms of your loan offered by the bank and calculate the cost of borrowing and its affordability to you under your circumstances.

• Student Loans. State laws often govern student loans and their terms. For example, unless state or provincial law prohibits it, a financial institution may apply compound interest to student loans and other types of loans. Compounding interest can be tricky for students and young professionals because it can mean an overpayment since you are paying interest on interest. High payments can be an uncomfortable burden if your career is just being built. Therefore, it would be relevant to read the terms of your loan agreement carefully and ensure you get loan terms tolerable for you.
• Personal Loans. This loans refer to a large group of credit products offered to individuals by banks and credit unions, other money lenders, etc.
  The lower the access requirements for a loan, the higher interest rates are usually offered. A high-interest rate can be indirectly increased even further. This happens through compound interest when you pay more than the interest accrued and the unpaid interest added to the principal amount.
  The lender must disclose all these terms, but the borrower's responsibility cannot be excluded. They must be attentive enough to read the loan terms and be disciplined to avoid falling into a financial trap.
• Mortgages. Mortgage loans offered by the banks usually mean significant amounts for an extended period. Therefore, it is essential to compare different repayment plans and see which payment is more favorable for you. With mortgage loans, the overpayment can be substantial. Therefore, you can request other repayment options from your lender.
  In a mortgage with monthly compounding, the outstanding interest is added to the principal amount once a month. The compounding interval can be weekly or daily, which you should check with your lender. The more frequent compounding intervals are, the more interest a lender earns.