Understanding Your Auto Loan Payment with SchoolsFirst
When you're ready to purchase a new or used vehicle, securing the right auto loan is a crucial step. SchoolsFirst Federal Credit Union offers competitive auto loan options to help members finance their dreams. This calculator is designed to give you a clear estimate of your potential monthly payments based on key loan parameters.
The calculation is based on the standard amortization formula for a fixed-rate loan. This formula helps determine the consistent monthly payment required to pay off both the principal amount borrowed and the accrued interest over the life of the loan.
How the Calculation Works:
The formula used is:
M = P [ i(1 + i)^n ] / [ (1 + i)^n – 1]
Where:
M = Your total monthly payment
P = The principal loan amount (the total amount you borrow for the car)
i = Your monthly interest rate. This is your annual interest rate divided by 12. For example, a 6% annual rate becomes 0.06 / 12 = 0.005 monthly.
n = The total number of payments over the loan's lifetime. This is your loan term in years multiplied by 12. For instance, a 5-year loan has 5 * 12 = 60 payments.
By inputting the Loan Amount, Annual Interest Rate, and Loan Term (in years), this calculator applies the formula to provide an estimated monthly payment (M).
Factors Affecting Your Auto Loan:
Credit Score: A higher credit score typically qualifies you for lower interest rates, significantly reducing your overall loan cost and monthly payments.
Loan Term: A longer loan term will result in lower monthly payments but will increase the total interest paid over time. A shorter term means higher monthly payments but less interest paid overall.
Down Payment: Making a down payment reduces the principal loan amount (P), which lowers your monthly payments and the total interest paid.
Vehicle Age and Type: Lenders may have different rates or terms based on whether the vehicle is new or used.
Use this calculator as a tool to help you budget and plan for your next vehicle purchase. For personalized loan offers and details specific to SchoolsFirst Federal Credit Union, please visit their official website or contact a loan specialist.
var slider = document.getElementById("loanTerm");
var output = document.getElementById("loanTermValue");
output.innerHTML = slider.value + " Years";
slider.oninput = function() {
output.innerHTML = this.value + " Years";
}
function calculateAutoLoan() {
var loanAmountInput = document.getElementById("loanAmount");
var interestRateInput = document.getElementById("interestRate");
var loanTermInput = document.getElementById("loanTerm");
var errorMessageDiv = document.getElementById("error-message");
var monthlyPaymentDiv = document.getElementById("result-monthly-payment");
errorMessageDiv.innerHTML = ""; // Clear previous errors
monthlyPaymentDiv.innerHTML = "$0.00"; // Reset result
var principal = parseFloat(loanAmountInput.value);
var annualRate = parseFloat(interestRateInput.value);
var loanTermYears = parseInt(loanTermInput.value);
// Input validation
if (isNaN(principal) || principal 100000) {
errorMessageDiv.innerHTML = "Please enter a valid loan amount between $100 and $100,000.";
return;
}
if (isNaN(annualRate) || annualRate 20) {
errorMessageDiv.innerHTML = "Please enter a valid annual interest rate between 0% and 20%.";
return;
}
if (isNaN(loanTermYears) || loanTermYears 7) {
errorMessageDiv.innerHTML = "Please select a loan term between 1 and 7 years.";
return;
}
var monthlyRate = annualRate / 100 / 12;
var numberOfPayments = loanTermYears * 12;
var monthlyPayment = 0;
if (monthlyRate === 0) {
// Handle 0% interest rate case
monthlyPayment = principal / numberOfPayments;
} else {
monthlyPayment = principal * (monthlyRate * Math.pow(1 + monthlyRate, numberOfPayments)) / (Math.pow(1 + monthlyRate, numberOfPayments) – 1);
}
// Check if calculation resulted in a valid number
if (isNaN(monthlyPayment) || !isFinite(monthlyPayment)) {
errorMessageDiv.innerHTML = "Calculation error. Please check your inputs.";
return;
}
monthlyPaymentDiv.innerHTML = "$" + monthlyPayment.toFixed(2);
}