Finance
Simple Interest Calculator
Work out simple interest in seconds. Enter your principal, the annual interest rate and the number of years, and ToolOrbit shows the interest earned plus the total amount you'll have. Uses the classic I = P·r·t formula — calculated instantly and privately in your browser.
Examples
Input · 1000 × 5 × 3 ÷ 100 = 150
Principal $1,000, rate 5%, time 3 years
Output
Interest $150.00, Total $1,150.00
How to use Simple Interest Calculator
Enter the principal
Type the starting amount of money you're investing or borrowing.
Add rate and time
Enter the annual interest rate as a percentage and the time in years.
Read the results
See the interest earned and the total amount (principal plus interest) instantly.
Why use this tool
Instant interest and total as you type
Uses the standard I = P·r·t formula
Clear breakdown of principal, rate and time
Everything runs locally — your numbers never leave your device
Frequently asked questions
Simple interest is calculated only on the original principal, using I = P·r·t ÷ 100. It does not compound, so interest does not earn further interest.
Simple interest applies the rate to the principal alone. Compound interest applies it to the principal plus previously accrued interest, so it grows faster over time.
Discussion
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