Financial Calculators
Simple Interest Calculator
Use this simple interest calculator entirely in your browser.
ResultInterest: $1,500.00
Final balance: $11,500.00
Visual summary
Simple-interest growth
The solid line shows the balance; the dashed line shows the unchanged principal.
| Period | Balance | Principal |
|---|---|---|
| Start | $10,000 | $10,000 |
| Year 1 | $10,500 | $10,000 |
| Year 2 | $11,000 | $10,000 |
| Year 3 | $11,500 | $10,000 |
Calculations happen locally in your browser.
How to use this calculator
- Enter the labelled values and review the live result.
- Review the live result and use Copy result when you need to share it.
How the calculation works
Interest equals principal × annual rate × years.
Formula
Interest equals principal × annual rate × years.
Step-by-step calculation
- Enter the labelled values and review the live result.
- Interest equals principal × annual rate × years.
- Check the displayed result, then copy it if needed.
Worked example
$10,000 at 5% for 3 years earns $1,500.
Risk guidance
Frequently asked questions
Does this tool send my inputs anywhere?
No. The interactive calculation runs in your browser and this site does not submit tool inputs to a backend.
How should I use the result?
Check that the entered units and values match your situation, especially around dates, breaks, and rounding.