Calculate your estimated monthly payment for a PenFed car loan.
5.0%
60 months
Your estimated monthly payment: $0.00
Understanding Your PenFed Car Loan Calculation
When you're looking to finance a vehicle with PenFed (Pentagon Federal Credit Union), understanding how your monthly car loan payment is calculated is crucial. This calculator helps you estimate your payments based on the loan amount, annual interest rate, and loan term.
The Math Behind the Payment
The standard formula for calculating a fixed-rate loan payment (like most car loans) is the annuity formula. This formula takes into account the principal loan amount, the interest rate, and the loan term to determine your fixed monthly installment.
The formula is as follows:
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)
i = Your monthly interest rate. This is calculated by dividing your annual interest rate by 12. For example, if your annual rate is 6%, your monthly rate (i) is 0.06 / 12 = 0.005.
n = The total number of payments over the loan's lifetime. This is calculated by multiplying the number of years of the loan by 12. For example, a 5-year loan has 5 * 12 = 60 payments.
How PenFed Car Loans Work
PenFed offers competitive auto loan rates and terms. The rates you receive typically depend on your creditworthiness, the loan term, and whether you're financing a new or used vehicle. Using this calculator can give you a realistic preview of what your payments might look like, helping you budget effectively before applying.
Using the Calculator
Loan Amount: Enter the total price of the vehicle you intend to finance, minus any down payment you plan to make.
Annual Interest Rate: Input the estimated Annual Percentage Rate (APR) you expect to receive from PenFed. This is a critical factor; a lower rate significantly reduces your total interest paid.
Loan Term: Specify the duration of the loan in months. Longer terms usually mean lower monthly payments but result in paying more interest over time. Shorter terms have higher payments but save you money on interest.
Why This Matters
By experimenting with different values, you can:
Determine an affordable monthly payment.
See how a small change in interest rate impacts your payment.
Compare different loan terms to find the best balance between payment amount and total interest paid.
Remember, this calculator provides an estimate. Your actual PenFed car loan payment may vary based on their final underwriting and specific loan product terms. It's always recommended to get pre-approved by PenFed for the most accurate figures.
function calculateCarLoan() {
var loanAmount = parseFloat(document.getElementById("loanAmount").value);
var annualInterestRate = parseFloat(document.getElementById("annualInterestRate").value);
var loanTerm = parseInt(document.getElementById("loanTerm").value);
var resultDisplay = document.getElementById("result").querySelector("span");
// Input validation
if (isNaN(loanAmount) || isNaN(annualInterestRate) || isNaN(loanTerm) || loanAmount <= 0 || annualInterestRate < 0 || loanTerm <= 0) {
resultDisplay.textContent = "Invalid input. Please enter valid numbers.";
return;
}
// Convert annual interest rate to monthly interest rate
var monthlyInterestRate = annualInterestRate / 100 / 12;
var monthlyPayment = 0;
if (monthlyInterestRate === 0) {
// Handle zero interest rate case
monthlyPayment = loanAmount / loanTerm;
} else {
// Calculate monthly payment using the annuity formula
var numerator = monthlyInterestRate * Math.pow(1 + monthlyInterestRate, loanTerm);
var denominator = Math.pow(1 + monthlyInterestRate, loanTerm) – 1;
monthlyPayment = loanAmount * (numerator / denominator);
}
// Format the result to two decimal places
resultDisplay.textContent = "$" + monthlyPayment.toFixed(2);
}
// Initialize range slider values on load if needed, or rely on default HTML values
document.addEventListener('DOMContentLoaded', function() {
var rateSlider = document.getElementById('annualInterestRate');
var rateValueSpan = document.getElementById('annualInterestRateValue');
var rateNumInput = document.getElementById('annualInterestRateNum');
rateValueSpan.textContent = rateSlider.value;
rateNumInput.value = rateSlider.value;
var termSlider = document.getElementById('loanTerm');
var termValueSpan = document.getElementById('loanTermValue');
var termNumInput = document.getElementById('loanTermNum');
termValueSpan.textContent = termSlider.value;
termNumInput.value = termSlider.value;
});