Simple Interest Calculator
Understanding Simple Interest
Simple interest is a straightforward method of calculating the interest charged on a loan or earned on an investment. It is calculated only on the initial amount of money, known as the principal. Unlike compound interest, simple interest does not include interest on previously earned interest, making it a simpler calculation.
The formula for simple interest is:
Simple Interest (SI) = (Principal Amount × Annual Interest Rate × Time) / 100
- Principal Amount (P): This is the initial sum of money borrowed or invested.
- Annual Interest Rate (R): This is the rate at which interest is charged or earned per year, expressed as a percentage.
- Time (T): This is the duration for which the money is borrowed or invested, usually in years.
To find the total amount to be repaid (for a loan) or the total value of an investment (for savings), you add the calculated simple interest to the original principal amount:
Total Amount = Principal Amount + Simple Interest
When is Simple Interest Used?
Simple interest is commonly used for short-term loans, such as:
- Personal loans
- Short-term business loans
- Some types of auto loans
- Savings accounts with very short terms
It's also a fundamental concept for understanding more complex interest calculations like compound interest.
Example Calculation:
Let's say you take out a personal loan of $5,000 (Principal) with an annual interest rate of 7% for 4 years.
- Principal (P) = $5,000
- Annual Interest Rate (R) = 7%
- Time (T) = 4 years
Using the simple interest formula:
SI = ($5,000 × 7 × 4) / 100
SI = $140,000 / 100
SI = $1,400
The total interest you would pay over 4 years is $1,400.
The total amount you would repay is:
Total Amount = $5,000 (Principal) + $1,400 (Interest)
Total Amount = $6,400
This calculator helps you quickly determine the simple interest and the total amount for your loan or investment scenarios.