Interest generated
This is the cost or return accumulated over the full term.
Finance
Simple interest calculator
Calculate the interest generated and the total to pay or receive, even when the rate and term use different periods.
Main calculation
How much interest is generated?
Enter the rate as you know it. The calculator automatically converts the term to the same period.
Publicidad
How to read the result
Simple interest keeps the principal that generates the return or cost fixed.
Total to pay or receive
Adds the initial principal and all interest generated.
Total interest over the term
Shows what percentage of principal the accumulated interest represents.
Simple interest formula
Interest = principal × rate per period × number of periods. The final amount is the initial principal plus the interest earned.
Need another type of calculation?
For installments that reduce the balance, use the loan calculator. To reinvest interest, use the compound interest calculator.
Frequently asked questions
What is the simple interest formula?
Simple interest is calculated by multiplying the initial principal by the rate per period and the number of periods. Interest is not added to principal to generate more interest.
How do I convert a monthly rate to an annual rate?
For simple interest, multiply the monthly rate by 12. For example, a 2% monthly simple rate equals 24% annually.
What is the difference between simple and compound interest?
With simple interest, only the initial principal earns interest. With compound interest, accumulated interest also earns interest.
What is the difference between using 360 and 365 days?
The commercial convention uses 360-day years and the civil convention uses 365. This choice can change the result when the term is in days and the rate is monthly or annual.
Can this calculator be used for loans?
It works for loans that calculate interest on the initial principal without partial payments. For installment loans with a declining balance, use a loan calculator.
Does simple interest include partial payments?
No. This calculator assumes the initial principal remains constant throughout the term.