Use our free Simple Interest Calculator to get a clear estimate in seconds. Enter your values and see an instant result. Create a free account if you want your inputs saved for next time.
How to use this simple interest calculator
- Enter each requested value using the units displayed beside the field.
- Select any options that match your situation, then choose Calculate result.
- Review the main answer and supporting values. Change any input to compare another scenario.
The formula
Interest = principal × annual rate × time. Final balance = principal + interest.
The calculator uses the full precision of your inputs and rounds only the values shown on screen. This helps avoid compounding rounding errors.
Worked example
$5,000 at 6% simple interest for 3 years earns $900 and finishes at $5,900.
Keep in mind: This result is an estimate for planning and education. It does not replace personalized financial, medical, legal, or other professional advice.