Financing a new or used car is a significant financial decision. An Auto Loan Calculator, like this one designed for potential AFCU members, helps you estimate your monthly payments and understand the total cost of your loan. This tool allows you to input key details about the loan you're considering and provides an immediate estimate, empowering you to budget effectively and make informed choices.
How the Calculation Works
The monthly payment for an auto loan is calculated using a standard loan amortization formula. The core components are:
Principal Loan Amount (P): The total amount of money you are borrowing for the car.
Annual Interest Rate (r): The yearly percentage charged by the lender. This needs to be converted to a monthly rate for the calculation.
Loan Term (n): The total duration of the loan, typically expressed in years, which is also converted to months.
The formula for the monthly payment (M) is:
M = P [ i(1 + i)^n ] / [ (1 + i)^n – 1]
Where:
P = Principal Loan Amount
i = Monthly Interest Rate (Annual Rate / 12)
n = Total Number of Payments (Loan Term in Years * 12)
This formula calculates the fixed amount you will pay each month to cover both the principal and the interest over the life of the loan.
Using This Calculator
Simply enter the following into the fields provided:
Car Loan Amount: The price of the car minus any down payment you plan to make.
Annual Interest Rate: The estimated APR (Annual Percentage Rate) you might qualify for. AFCU offers competitive rates, so check their current offerings.
Loan Term: The number of years you plan to finance the vehicle. Shorter terms mean higher monthly payments but less total interest paid. Longer terms mean lower monthly payments but more total interest.
Clicking "Calculate Payment" will provide an estimate of your monthly payment, the total amount of interest paid over the loan's life, and the total amount repaid.
Why Use an Auto Loan Calculator?
Budgeting: Helps you determine if a car fits within your monthly budget.
Comparison: Allows you to compare different loan scenarios (e.g., varying interest rates or terms) to find the most affordable option.
Negotiation Power: Knowing your potential payments can assist you when negotiating with dealerships.
Financial Planning: Understand the long-term cost of your vehicle purchase.
This calculator provides an estimate. Actual loan terms, rates, and final payments may vary based on your creditworthiness, specific loan product, and final agreement with America First Credit Union. It's always recommended to get pre-approved and discuss your options directly with AFCU.
function updateInterestRate(value) {
var input = document.getElementById('interestRate');
input.value = value;
calculateCarLoan();
}
function updateLoanTerm(value) {
var input = document.getElementById('loanTerm');
input.value = value;
calculateCarLoan();
}
function calculateCarLoan() {
var loanAmountInput = document.getElementById('loanAmount');
var interestRateInput = document.getElementById('interestRate');
var loanTermInput = document.getElementById('loanTerm');
var resultDiv = document.getElementById('result');
var P = parseFloat(loanAmountInput.value);
var annualRate = parseFloat(interestRateInput.value);
var termYears = parseInt(loanTermInput.value);
if (isNaN(P) || isNaN(annualRate) || isNaN(termYears) || P <= 0 || annualRate <= 0 || termYears <= 0) {
resultDiv.style.display = 'none';
return;
}
var i = (annualRate / 100) / 12; // Monthly interest rate
var n = termYears * 12; // Total number of payments
var monthlyPayment = 0;
if (i === 0) { // Handle zero interest rate
monthlyPayment = P / n;
} else {
monthlyPayment = P * (i * Math.pow(1 + i, n)) / (Math.pow(1 + i, n) – 1);
}
var totalPayment = monthlyPayment * n;
var totalInterest = totalPayment – P;
document.querySelector('.monthly-payment').innerText = '$' + monthlyPayment.toFixed(2);
document.querySelector('.total-payment').innerText = 'Total Paid: $' + totalPayment.toFixed(2);
document.querySelector('.total-interest').innerText = 'Total Interest: $' + totalInterest.toFixed(2);
resultDiv.style.display = 'block';
}
// Initial calculation on page load
window.onload = calculateCarLoan;