Loan Calculator
Estimate fixed monthly principal and interest payments and total borrowing cost.
Money & Planning · FREE TO USE
Simple Interest Calculator
Calculate interest applied only to the original principal.
02EXAMPLE RESULT
Final amount
1,150
currency units
Simple interest150currency units
Original principal1,000currency units
Time period3years
Results update as you type. Calculate adds a snapshot to your history.
How this calculation works
Simple interest does not earn interest on accumulated interest. Time is entered in years; for example, six months is 0.5 years. This is a constant-rate model and does not reproduce lenders’ daily accrual conventions, fees, or repayment schedules.
Interest = principal × annual rate ÷ 100 × years. Final amount = principal + interest.
Your calculation, step by step
- 1,000 × 5% × 3 years = 150 interest.
- Add the interest to the original principal.
A worked example
1,000 at 5% simple annual interest for 3 years earns 150, giving 1,150 in total.