This is an estimate and may not reflect actual dealer pricing or financing offers.
Understanding Your GM Vehicle Payment
Purchasing a new or used vehicle from General Motors (GM) involves several financial considerations, with the monthly payment being a primary concern for most buyers. This calculator is designed to provide an estimated monthly payment based on key financial inputs, helping you budget and plan for your next GM vehicle, whether it's a Chevrolet, GMC, Buick, or Cadillac.
The calculation uses a standard auto loan amortization formula to determine your estimated monthly payment. Understanding these components can help you negotiate better terms and make informed decisions.
Key Factors in the Calculation:
Vehicle Price: This is the sticker price or agreed-upon sale price of the vehicle before any incentives, taxes, or fees.
Down Payment: The amount of money you pay upfront at the time of purchase. A larger down payment reduces the total loan amount, leading to lower monthly payments.
Loan Term: The duration of the loan, measured in months. Longer loan terms typically result in lower monthly payments but mean you'll pay more interest over the life of the loan.
Annual Interest Rate (APR): This is the annual cost of borrowing money, expressed as a percentage. A lower APR significantly reduces your total interest paid and your monthly payment.
How the Calculation Works:
The formula used to calculate the monthly payment (M) for an auto loan is derived from the standard loan amortization formula:
M = P [ i(1 + i)^n ] / [ (1 + i)^n – 1]
Where:
M = Your monthly payment
P = The principal loan amount (Vehicle Price – Down Payment)
i = Your monthly interest rate (Annual Interest Rate / 12 / 100)
n = The total number of payments (Loan Term in Months)
For example, if the Principal Loan Amount (P) is $30,000, the Annual Interest Rate is 7.5%, and the Loan Term is 60 months:
The monthly interest rate (i) would be 7.5 / 12 / 100 = 0.00625
The number of payments (n) is 60
Plugging these values into the formula would yield the estimated monthly payment.
Tips for GM Buyers:
Check GM Offers: GM often provides special financing rates (sometimes as low as 0% APR) on select models. Always check for these manufacturer incentives, as they can significantly reduce your total cost.
Get Pre-Approved: Obtaining pre-approval from your bank or credit union before visiting a dealership can give you leverage and a benchmark for the financing terms offered by GM Financial.
Negotiate Price First: Focus on agreeing on the vehicle's purchase price before discussing financing.
Consider Total Cost: While a lower monthly payment is attractive, consider the total interest paid over the loan term. A shorter loan term or a larger down payment can save you money in the long run.
Use this calculator as a tool to estimate potential payments, but always consult with a GM dealership and GM Financial for precise figures and available offers.
var vehiclePriceInput = document.getElementById("vehiclePrice");
var downPaymentInput = document.getElementById("downPayment");
var loanTermInput = document.getElementById("loanTerm");
var loanTermValueSpan = document.getElementById("loanTermValue");
var loanTermNumberInput = document.getElementById("loanTermNumber");
var annualInterestRateInput = document.getElementById("annualInterestRate");
var annualInterestRateValueSpan = document.getElementById("annualInterestRateValue");
var annualInterestRateNumberInput = document.getElementById("annualInterestRateNumber");
var resultDiv = document.getElementById("result");
var resultValueDiv = document.getElementById("result-value");
var errorMessageDiv = document.getElementById("error-message");
// Update slider value display and hidden input for range inputs
loanTermInput.oninput = function() {
loanTermValueSpan.innerHTML = this.value;
loanTermNumberInput.value = this.value;
}
annualInterestRateInput.oninput = function() {
annualInterestRateValueSpan.innerHTML = this.value;
annualInterestRateNumberInput.value = this.value;
}
function calculatePayment() {
errorMessageDiv.style.display = 'none';
resultDiv.style.display = 'none';
var vehiclePrice = parseFloat(vehiclePriceInput.value);
var downPayment = parseFloat(downPaymentInput.value);
var loanTerm = parseFloat(loanTermNumberInput.value); // Use the hidden number input
var annualInterestRate = parseFloat(annualInterestRateNumberInput.value); // Use the hidden number input
// Input validation
if (isNaN(vehiclePrice) || vehiclePrice <= 0) {
errorMessageDiv.innerHTML = "Please enter a valid Vehicle Price.";
errorMessageDiv.style.display = 'block';
return;
}
if (isNaN(downPayment) || downPayment < 0) {
errorMessageDiv.innerHTML = "Please enter a valid Down Payment.";
errorMessageDiv.style.display = 'block';
return;
}
if (isNaN(loanTerm) || loanTerm <= 0) {
errorMessageDiv.innerHTML = "Please enter a valid Loan Term in months.";
errorMessageDiv.style.display = 'block';
return;
}
if (isNaN(annualInterestRate) || annualInterestRate vehiclePrice) {
errorMessageDiv.innerHTML = "Down Payment cannot be greater than Vehicle Price.";
errorMessageDiv.style.display = 'block';
return;
}
var principal = vehiclePrice – downPayment;
var monthlyInterestRate = annualInterestRate / 12 / 100;
var numberOfPayments = loanTerm;
var monthlyPayment = 0;
if (monthlyInterestRate === 0) {
monthlyPayment = principal / numberOfPayments;
} else {
monthlyPayment = principal * (monthlyInterestRate * Math.pow(1 + monthlyInterestRate, numberOfPayments)) / (Math.pow(1 + monthlyInterestRate, numberOfPayments) – 1);
}
// Check if calculation resulted in a valid number
if (isNaN(monthlyPayment) || !isFinite(monthlyPayment)) {
errorMessageDiv.innerHTML = "Calculation error. Please check your inputs.";
errorMessageDiv.style.display = 'block';
return;
}
resultValueDiv.innerHTML = "$" + monthlyPayment.toFixed(2);
resultDiv.style.display = 'block';
}