How to use the Simple Interest Calculator
Enter the principal amount, annual interest rate and time in years and the result appears straight away. Everything runs in your browser, so nothing you type is uploaded.
The formula
Interest = principal × rate × time ÷ 100.
Examples
- 1,000 at 5% for 3 years
Simple interest: 150 Final amount: 1,150
- 25,000 at 7.5% for 2 years
Simple interest: 3,750 Final amount: 28,750
- 4,800 at 3.2% for 10 years
Simple interest: 1,536 Final amount: 6,336
Limitations and assumptions
Results are estimates for general information. Check assumptions and inputs before relying on them.
Frequently asked questions
What is the simple interest formula?
Interest = principal × rate × time ÷ 100, with the rate as a yearly percentage.
How is it different from compound interest?
Compound interest adds earned interest to the balance, so it grows faster over longer periods.
Where is simple interest used?
Short term loans, some bonds, auto loans and student loans often use simple interest.
How do I enter months?
Convert to years, for example 6 months is 0.5.