Principal Amount (Rs)
1,0001 Crore
Interest Rate (% per annum)
120
Time Period (Years)
130
Principal Amount Interest Earned
What is a Simple Interest Calculator?
Simple Interest is the most basic way to calculate interest on a principal amount — it’s charged (or earned) only on the original principal, and does not compound. This means the interest amount stays the same every year, unlike compound interest where interest is also earned on previously accumulated interest.
Simple interest is commonly used for certain short-term loans, some bonds, and basic savings instruments. It’s important to understand because it grows your money (or your debt) much more slowly than compound interest over long periods.
How Simple Interest is Calculated
SI = (P × R × T) / 100
SI = Simple interest earned or payable
P Principal amount
R Annual interest rate (as a percentage, not a decimal)
T Time period in years
Note: Because simple interest doesn’t compound, the interest earned each year is identical — it does not grow faster over time the way compound interest does. Most mutual fund and long-term investment products use compound interest, not simple interest.
Example: A principal of Rs. 1,00,000 at 8% per annum for 5 years earns Rs. 40,000 in simple interest, for a total amount of Rs. 1,40,000.
Frequently Asked Questions
What is a Simple Interest calculator?
It calculates interest earned or owed based only on the original principal amount, without compounding.
How is simple interest calculated?
SI = (P x r x t) / 100, where P is the principal, r is the annual interest rate, and t is the time period in years.
How is simple interest different from compound interest?
Simple interest is calculated only on the original principal for the entire period, while compound interest is calculated on the principal plus any previously accumulated interest, resulting in faster growth over time.
Where is simple interest commonly used?
Simple interest is commonly used for short-term loans, certain fixed deposits, and some types of bonds.
Is the simple interest calculator result exact?
Yes, for products that genuinely use simple interest; however, most investment products like mutual funds and many loans use compound interest instead.