Installment Calculator
Calculate monthly or periodic installment payments with complete amortization schedule
An installment loan is repaid over time with a set number of scheduled payments. Use this calculator to determine your payment amount, total interest cost, and view a complete amortization schedule.
Installment Calculator
About Installment Payments
Installment payments are a fixed amount paid at regular intervals over a specified period until a loan is fully repaid. They consist of both principal repayment and interest on the outstanding balance.
This calculator uses the standard installment loan formula:
Payment = P × [r(1+r)^n] ÷ [(1+r)^n-1]
Where:
P = Principal amount (loan amount)
r = Periodic interest rate (annual rate ÷ number of payment periods per year)
n = Total number of payments (number of years × payment frequency)
As you make payments, each payment first covers the interest due on the outstanding balance, with the remainder reducing the principal. This is why early payments consist mostly of interest, while later payments primarily reduce the principal.