Interest: Explained

What is it, how to calculate it, formula, why it's important

Have you ever been so passionate about something that you can talk about it for hours? That's me with interest rates. I know it may sound boring, but trust me when I say it's far from it. Interest rates are like the heart of the economy, and they affect almost every aspect of our lives. From the price we pay for our loans to the cost of our groceries, interest rates have a tremendous impact on our day-to-day living.

What are interest rates?

Let me start from the beginning. Interest rates are the cost of borrowing money. When you borrow money from a bank or lender, you agree to pay back the borrowed amount plus interest - a fee for the service of borrowing. The interest rate is usually expressed as a percentage of the amount borrowed and is calculated based on several factors.

How do interest rates affect the economy?

Interest rates play a crucial part in the economy. When the economy is down, central banks lower interest rates to encourage spending and borrowing. This increases the money flow in the economy and helps businesses to grow. On the other hand, when the economy is strong and showing signs of inflation, central banks raise interest rates to slow down it down. This is done to avoid any hyperinflation, which can harm the economy in the long run.

In simple terms, interest rates impact the economy by adjusting the amount of money flowing in and out. When interest rates are high, spending and borrowing decrease, and the money supply in the economy shrinks. Conversely, when interest rates are low, spending and borrowing increase, and the money supply in the economy grows.

How do interest rates affect me?

Interest rates influence almost every aspect of your life. Here are a few examples:


Interest rates are a crucial factor when obtaining a loan. Whether you're buying a car or a house, the interest rate will significantly impact your monthly payments and your overall cost of borrowing. Also, the length of the loan will determine the total cost of borrowing as the loan term influences the interest rate charged. Short term loans come with higher interest rates and vice versa.

Credit Cards

If you have a credit card, you're likely aware of the astronomical interest rates attached to it. Credit card interest rates are usually higher than other types of loans because they come with no collateral and a higher rate of default. Your credit score can also play a part in the interest rate you're charged, so keep that in mind.


Interest rates play a role in how much interest your savings accounts earn. When interest rates are high, your savings account will earn more interest. Conversely, low-interest rates can result in minimal earnings for your savings.

Inflation and Investments

Inflation rates and interest rates often have an inverse relationship, which means when interest rates increase, inflation decreases. This helps to stabilize the economy as people are encouraged to invest their money. When the interest rates go up, the market becomes more competitive, and the stock market becomes less attractive to investors.


Interest rates may seem like a small technicality in finance, but they have an enormous influence on our lives. They have a significant impact on the economy, individual savings, and even our daily expenditures. Being aware of the interest rates around you can help you save money on interest payments, make informed financial decisions, and take advantage of investment opportunities.

So, next time someone tells you that interest rates are boring and that they don't care, you can enlighten them with everything you've learned here. Who knows, maybe you'll find someone as passionate about interest rates as I am.

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