Finance
Simple Interest Calculator
Work out the interest earned or paid on a principal amount at a fixed rate over time.
The interest figure is the extra amount earned or paid on top of the principal, and the total is the principal plus that interest.
Formula
Interest equals principal times rate times time, divided by 100.
How it works
Enter the starting amount, the yearly rate, and how many years the money is held. The result shows interest alone plus the total amount. It assumes the rate never changes and no compounding happens.
Worked example
For example, $10,000 at 5% for 3 years gives interest of $10,000 × 5 ÷ 100 × 3 = $1,500, so the total is $10,000 + $1,500 = $11,500.
FAQs
Simple interest differs from compound interest because it is charged only on the original principal, never on interest already earned.
Why is the rate divided by 100?
Percent means per hundred, so 5% is 0.05 in the calculation.
Can I use months instead of years?
Yes — convert months to years first, for example 6 months is 0.5 years.
Are these figures financial advice?
No — they are estimates for planning only, not financial advice. Check with a qualified adviser for decisions involving large sums.
Estimates only, not financial advice. Figures are approximate and do not include all fees, taxes, or changing rates unless stated.
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