Calculadora de Empréstimo
- Created by
- Renato Passos, Eng. de Software
- Reviewed by
- Renato Passos, Eng. de Software
Last updated: Apr 18, 2026
Formula
PMT = P·r·(1+r)ⁿ / ((1+r)ⁿ − 1)
About this calculator
The Loan Calculator allows you to estimate the monthly installment, total amount paid, and total interest for any loan. Simply enter the loan amount, monthly interest rate, and number of installments. The tool uses the constant payment formula (Price) to calculate the exact installment value considering compound interest.
The calculation is based on the formula PMT = P × r × (1+r)^n / ((1+r)^n − 1), where P is the principal amount, r is the monthly interest rate (in decimal), and n is the number of installments. The result shows the installment amount, total paid (installment × number of installments), and total interest (total paid minus principal).
Use this calculator when planning a vehicle or home financing, or any personal credit. It helps compare different term and rate scenarios, making it easier to choose the best option for your budget. It is also useful for simulating early payment or understanding the impact of interest rates.
Cautions: the interest rate entered must be monthly and equivalent to the effective rate in the contract. In some cases, additional fees (insurance, charges) are not included in the calculation. The Price system generates fixed installments, but some loans use different amortization methods (e.g., SAC). Always check the actual contract conditions.
Frequently asked questions
What does PMT mean in the loan formula?
PMT is the constant monthly installment value, calculated using the Price formula. It is the amount you will pay each month until the loan is paid off.
Can I use this calculator for a mortgage?
Yes, as long as the interest rate and term are compatible. Remember that mortgages often have higher rates and longer terms, and may include mandatory insurance.
Does the calculator consider compound interest?
Yes, the Price formula uses compound interest, which is standard for most loans and financing.
What if the interest rate is annual?
Convert the annual rate to a monthly rate using the formula: monthly rate = (1 + annual rate)^(1/12), 1. Enter the decimal value in the rate field.
Does the result include administrative fees or insurance?
No. The calculation only considers principal and interest. Extra fees must be added manually to get the actual cost.