Calculate how long it takes to pay off your car by making extra payments.
Your Car Payoff Estimate
Understanding Your Car Payoff
Paying off your car loan faster can save you a significant amount of money on interest and free up your budget sooner. This calculator helps you estimate the impact of making additional payments towards your car loan, considering the current balance, your regular payment, any extra amount you can afford, and the loan's annual interest rate.
How it Works:
The calculator uses an iterative approach to simulate your loan repayment month by month. Here's a breakdown of the core concepts:
Current Loan Balance: The total amount you still owe on your car loan.
Current Monthly Payment: The fixed amount you are currently paying each month.
Extra Monthly Payment: Any additional amount you choose to pay above your regular monthly payment. This is the key variable for accelerating payoff.
Annual Interest Rate: The yearly percentage charged by the lender. This is converted to a monthly rate for calculations.
The Math Behind the Calculation:
The calculator simulates each month's payment. For each month:
Calculate Interest for the Month: The current outstanding balance is multiplied by the monthly interest rate (Annual Interest Rate / 12).
Add Interest to Balance: This calculated interest is added to your loan balance.
Apply Total Payment: Your total payment for the month (Current Monthly Payment + Extra Monthly Payment) is subtracted from the balance.
Track Progress: This process repeats until the loan balance reaches zero or less.
The total time to payoff is determined by counting the number of months it takes to reach a zero balance. The total interest paid is the sum of all the monthly interest amounts calculated throughout the loan's life.
Why Use This Calculator?
Visualize Savings: See exactly how much interest you can save by making extra payments.
Plan Your Finances: Determine how much extra you need to pay to reach your payoff goal by a specific date.
Accelerate Freedom: Understand the quickest path to becoming car-payment-free.
Compare Scenarios: Easily adjust the extra payment amount to see different payoff timelines and savings.
By inputting your loan details and experimenting with different extra payment amounts, you can gain valuable insights into optimizing your car loan repayment strategy and achieve financial freedom faster.
function calculateCarPayoff() {
var currentBalance = parseFloat(document.getElementById("currentBalance").value);
var currentMonthlyPayment = parseFloat(document.getElementById("currentMonthlyPayment").value);
var extraPayment = parseFloat(document.getElementById("extraPayment").value);
var annualInterestRate = parseFloat(document.getElementById("annualInterestRate").value);
var resultDiv = document.getElementById("result");
var payoffResultElement = document.getElementById("payoffResult");
var totalInterestPaidElement = document.getElementById("totalInterestPaid");
var originalPayoffTimeElement = document.getElementById("originalPayoffTime");
// Clear previous results
payoffResultElement.textContent = "";
totalInterestPaidElement.textContent = "";
originalPayoffTimeElement.textContent = "";
// Input validation
if (isNaN(currentBalance) || isNaN(currentMonthlyPayment) || isNaN(extraPayment) || isNaN(annualInterestRate)) {
payoffResultElement.textContent = "Please enter valid numbers for all fields.";
return;
}
if (currentBalance <= 0 || currentMonthlyPayment <= 0 || annualInterestRate < 0 || extraPayment (originalBalance * monthlyInterestRate)) { // Check if payment covers interest
while (tempBalanceOriginal > 0) {
var interestForMonthOriginal = tempBalanceOriginal * monthlyInterestRate;
tempBalanceOriginal -= currentMonthlyPayment – interestForMonthOriginal;
totalInterestAccumulated += interestForMonthOriginal; // This will be overridden for accelerated calculation, but used for original calculation
originalMonths++;
if (originalMonths > 10000) { // Prevent infinite loops for impossible scenarios
originalPayoffTimeElement.textContent = "Original Payoff Time: Could not be calculated (payment too low or extremely long term).";
break;
}
}
originalPayoffTimeElement.textContent = "Original Payoff Time (without extra): " + originalMonths + " months";
} else {
originalPayoffTimeElement.textContent = "Original Payoff Time (without extra): Not calculable (monthly payment does not cover interest).";
}
// Calculate accelerated payoff time
var tempBalanceAccelerated = balance;
var monthsAccelerated = 0;
var totalInterestPaidAccelerated = 0;
if (totalMonthlyPayment 0) {
var interestForMonth = tempBalanceAccelerated * monthlyInterestRate;
totalInterestPaidAccelerated += interestForMonth;
tempBalanceAccelerated = tempBalanceAccelerated + interestForMonth – totalMonthlyPayment;
monthsAccelerated++;
if (monthsAccelerated > 10000) { // Safety break for very long terms
payoffResultElement.textContent = "Calculation exceeded maximum iterations. Your loan may take a very long time to pay off.";
totalInterestPaidElement.textContent = "";
break;
}
}
if (monthsAccelerated <= 10000) {
payoffResultElement.textContent = "Estimated Payoff Time: " + monthsAccelerated + " months";
totalInterestPaidElement.textContent = "Total Interest Paid: $" + totalInterestPaidAccelerated.toFixed(2);
}
}