Lease Implicit Interest Rate Calculator

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Auto Loan Payment Calculator

Enter 0 if paid off.
36 Months (3 Years) 48 Months (4 Years) 60 Months (5 Years) 72 Months (6 Years) 84 Months (7 Years)

Estimated Monthly Payment

$0.00

Net Loan Amount: $0.00
Trade-in Equity: $0.00
Total Interest Paid: $0.00
Total Cost of Car: $0.00

*Estimated payment for principal and interest only. Does not include taxes, title, license, or insurance.

function calculateCarLoan() { var priceInput = document.getElementById('clc-vehicle-price').value; var tradeValueInput = document.getElementById('clc-trade-in-value').value; var tradeOwedInput = document.getElementById('clc-trade-in-owed').value; var downPaymentInput = document.getElementById('clc-down-payment').value; var rateInput = document.getElementById('clc-interest-rate').value; var termInput = document.getElementById('clc-loan-term').value; var price = parseFloat(priceInput) || 0; var tradeValue = parseFloat(tradeValueInput) || 0; var tradeOwed = parseFloat(tradeOwedInput) || 0; var downPayment = parseFloat(downPaymentInput) || 0; var annualRate = parseFloat(rateInput) || 0; var months = parseInt(termInput) || 60; var resultDiv = document.getElementById('clc-result'); if (price <= 0 || months <= 0) { alert("Please enter a valid vehicle price and loan term."); resultDiv.style.display = 'none'; return; } // Calculate Net Trade Equity (Can be negative) var tradeEquity = tradeValue – tradeOwed; // Calculate Principal (Loan Amount) var principal = price – downPayment – tradeEquity; if (principal 0) { var monthlyRate = (annualRate / 100) / 12; // Standard Amortization Formula: M = P [ r(1+r)^n ] / [ (1+r)^n – 1] monthlyPayment = principal * (monthlyRate * Math.pow(1 + monthlyRate, months)) / (Math.pow(1 + monthlyRate, months) – 1); var totalPaid = monthlyPayment * months; totalInterest = totalPaid – principal; } else { // 0% APR case monthlyPayment = principal / months; totalInterest = 0; } var totalCost = downPayment + tradeValue + totalInterest + (principal > 0 ? principal : 0); var currencyFormat = new Intl.NumberFormat('en-US', { style: 'currency', currency: 'USD' }); document.getElementById('clc-monthly-payment-display').innerHTML = currencyFormat.format(monthlyPayment); document.getElementById('clc-principal-display').innerHTML = currencyFormat.format(principal); document.getElementById('clc-equity-display').innerHTML = currencyFormat.format(tradeEquity); document.getElementById('clc-total-interest-display').innerHTML = currencyFormat.format(totalInterest); // Total cost here means Price + Interest (what you paid in total for the asset) document.getElementById('clc-total-cost-display').innerHTML = currencyFormat.format(price + totalInterest); resultDiv.style.display = 'block'; }

Comprehensive Car Loan Payment Calculator: Trade-ins, Down Payments, and Negative Equity

Purchasing a new or used vehicle involves more than just looking at the sticker price. Most buyers finance their purchase, meaning the monthly payment determines affordability. Furthermore, factors like trading in an old car—especially one you still owe money on—can significantly complicate the math. Our Comprehensive Car Loan Payment Calculator is designed to handle these real-world scenarios, giving you an accurate picture of your potential monthly costs and the total interest you will pay over the life of the loan.

How Factors Impact Your Auto Loan

Understanding the inputs in this calculator will help you negotiate a better deal at the dealership.

1. The Trade-in Equity Factor

Your trade-in can either be a huge asset or a liability. This is determined by your "equity."

  • Positive Equity: If your car is worth $15,000 and you only owe $10,000, you have $5,000 in positive equity. This acts like an additional down payment, reducing the amount you need to borrow for the new car.
  • Negative Equity (Being "Underwater"): If your car is worth $15,000 but you still owe $20,000, you have -$5,000 in negative equity. To buy a new car, this $5,000 debt doesn't disappear; it must be rolled on top of the price of the new vehicle, increasing your loan principal and your monthly payments.

2. The Down Payment

A cash down payment reduces the principal loan amount dollar-for-dollar. By borrowing less, you pay less interest over the life of the loan. A substantial down payment can sometimes help you secure a lower interest rate from lenders and can offset negative equity from a trade-in.

3. Interest Rate (APR) and Loan Term

The Annual Percentage Rate (APR) is the cost of borrowing money. A lower score generally secures a lower APR. The loan term is how long you have to repay the loan, typically ranging from 36 to 84 months.

  • Shorter Terms (e.g., 36-48 months): Have higher monthly payments but significantly lower total interest costs.
  • Longer Terms (e.g., 72-84 months): Lower the monthly payment, making the car seem more affordable, but drastically increase the total amount of interest paid over time. Longer terms also increase the risk of being "underwater" on your loan later.

Realistic Example Calculation

Let's look at a common scenario involving negative equity to see how it affects payment.

  • Vehicle Price: $35,000 (The new SUV you want)
  • Trade-in Value: $12,000 (Offer for your old sedan)
  • Amount Owed on Trade: $15,000 (You are underwater by $3,000)
  • Cash Down Payment: $2,000
  • Interest Rate: 6.5% APR
  • Loan Term: 60 Months

In this scenario, the $3,000 of negative equity is added to the new car price. The $2,000 cash down payment helps offset this. The net amount financed would be approximately $36,000. Using the calculator, the estimated monthly payment would be roughly $704.55, and you would pay over $6,200 in total interest over the five years.

Use the calculator above to experiment with different down payments and loan terms to find the balance that fits your budget before you visit the showroom.

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