Interest Calculator
Interest = Principal × Rate ÷ 100 × Time1000 × 5 ÷ 100 × 3 = $150
Free online tool
Interest Calculator
Enter the principal, rate and time to find the interest amount and total value.
Instant calculation
Calculate Simple Interest
Enter principal, rate and time to find interest.
Your result
Calculation
Your numbers stay in this browser. Nothing is uploaded or saved.
Three clear steps
How to use this calculator
- 01
Enter the principal
Type the starting amount of money.
- 02
Enter rate and time
Provide the annual interest rate and the number of years.
- 03
See interest and total
Calculate to see the interest amount and total value.
The formula
How this calculation works
Multiply the principal by the annual interest rate (as a decimal) and then by the number of years. Total = Principal + Interest.
Check the method
Worked examples
Each example follows the same formula used by the calculator.
How much interest on $1,000 at 5% for 3 years?
1000 × 5 ÷ 100 × 3 = $150$150 interest; total $1,150Common questions
Questions about this calculation
What is the Interest Calculator?
The Interest Calculator helps you calculate simple interest earned or owed on a principal amount. Enter your values and select Calculate to get an instant result.
How is the result calculated?
Multiply the principal by the annual interest rate (as a decimal) and then by the number of years. Total = Principal + Interest.
Can you show an example?
Example: How much interest on $1,000 at 5% for 3 years? — $150 interest; total $1,150.
Is my data saved when I use the Interest Calculator?
No. All calculations run locally in your browser. Your inputs and results are never uploaded, stored or shared with anyone.
Is the Interest Calculator free to use?
Yes. The Interest Calculator is completely free. No account, sign-up or payment is required. It works on mobile, tablet and desktop.
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