Simple Interest

Calculate standard interest on loans or savings.

Formula & Methodology

Simple interest I = P × r × t, where P is principal, r is the annual rate, and t is years.

Worked Example

$5,000 at 5% simple interest for 3 years earns $750.

Frequently Asked Questions

How is simple interest different from compound interest?

Simple interest is calculated only on the original principal, while compound interest is calculated on the principal plus accumulated interest.

Where is simple interest used?

It is common for short-term personal loans, auto loans, and some bonds. Most savings accounts use compound interest instead.

Is the rate annual?

Yes. The rate is an annual percentage, and the time is in years (or fractions of a year).

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