Simple interest calculator
Work out the interest on a loan or deposit when interest is not added to the balance.
InterestUSD 1,800
- Total amount
- USD 11,800
- Interest each year
- USD 600
- PrincipalUSD 10,00085%
- InterestUSD 1,80015%
- Total amount
- Simple interest is charged on the original amount only, so it does not grow on itself.
About this calculator
Simple interest is charged only on the amount you first lend or borrow. It does not earn interest on itself, so it grows in a straight line.
Enter the principal, the yearly rate and the time to see the interest and the total.
How it works
- Interest = principal × rate × time.
- The rate is a yearly rate, so months are converted into years.
- Total = principal + interest.
Common questions
- What is the simple interest formula?
- Interest = P × R × T, where P is the principal, R the yearly rate as a decimal and T the time in years.
- How is simple interest different from compound interest?
- Simple interest uses only the original amount. Compound interest also earns interest on interest already added, so it grows faster over time.