Formula Used
Monthly payment = P × [r(1 + r)^n] ÷ [(1 + r)^n − 1]
P = principal, r = periodic interest rate, n = number of payments.
How the formula is applied
The calculation links Loan amount ($), Interest rate (%) and Loan term (years) to monthly car payment. This form starts from loan principal, rather than computing a dealer purchase settlement. Enter the amount remaining after your separate down-payment and trade-in calculation.