Simple Interest Calculator
Watch your money grow over time!
The money you start with.
How fast it grows per year.
How long you wait.
Your Money Growth
Understanding Simple Interest
Welcome to the ultimate math helper! Have you ever wondered how banks give you extra money just for keeping your savings with them? Or how much extra you might have to pay back if you borrow money? That is exactly what our Simple Interest Calculator is designed to figure out. Interest is essentially the “rent” paid for using money. If you lend money to the bank (by depositing it), they pay you. If you borrow from them, you pay them!
In middle school math, we learn a very specific formula to solve these problems. Using a Simple Interest Calculator helps you visualize this formula in action. The formula is I = P × R × T.
The starting amount of money.
The percentage charged per year.
How many years the money grows.
Simple Interest means the interest is only calculated on the original amount (the Principal). It does not grow as fast as “Compound Interest,” where you earn interest on your interest, but it is the perfect place to start learning about finance. This Simple Interest Calculator shows you the straight-line growth of your money.
Frequently Asked Questions (FAQ)
How do I convert the rate to a decimal?
Great question! In the formula, R usually needs to be a decimal. For example, 5% becomes 0.05. However, our Simple Interest Calculator does this math for you automatically, so you can just type “5”!
What if time is in months?
The standard formula uses years. If you have months, divide by 12. For example, 6 months is 6/12, or 0.5 years.
Pro Tip: Use this Simple Interest Calculator to check your homework answers, but make sure you write down the steps (I = P × R × T) to get full credit in class!