Simple Interest Calculator
Result
10,000.00
Principal
2,100.00
Simple Interest
12,100.00
Total Amount
What is Simple Interest?
Simple Interest (SI) is a method of calculating interest where the interest is computed only on the original principal amount, not on any previously earned interest. It is the most straightforward form of interest calculation and is commonly used for short-term loans, vehicle loans, and some savings instruments.
Unlike compound interest, simple interest does not grow exponentially — it increases linearly with time, making it easier to predict and calculate.
Where is Simple Interest Used?
- Short-term personal loans and consumer finance
- Car/vehicle loans (in some countries)
- Certificates of deposit with fixed simple interest payouts
- Treasury bills and government securities
- Educational and microfinance loans
Frequently Asked Questions
What is the difference between simple and compound interest?
Simple interest is calculated only on the original principal. Compound interest is calculated on the principal plus any accumulated interest from prior periods. Over time, compound interest produces significantly higher returns.
How do I calculate simple interest manually?
Use the formula SI = (P × R × T) / 100. For example, 10,000 at 8% for 3 years: SI = (10,000 × 8 × 3) / 100 = 2,400. Total amount = 10,000 + 2,400 = 12,400.
Is simple interest better for borrowers or lenders?
Simple interest is generally better for borrowers as they pay less total interest compared to compound interest on the same loan. For lenders/investors, compound interest is more beneficial as it generates higher returns.
SI Formula
SI = (P × R × T) / 100
Total = P + SI