Fixed to Floating Interest Rate Calculator

Auto Loan Payment Calculator

36 Months (3 Years) 48 Months (4 Years) 60 Months (5 Years) 72 Months (6 Years) 84 Months (7 Years)

function calculateAutoLoan() { // 1. Get Input Values var price = parseFloat(document.getElementById('alc-price').value) || 0; var taxRate = parseFloat(document.getElementById('alc-sales-tax').value) || 0; var downPayment = parseFloat(document.getElementById('alc-down-payment').value) || 0; var tradeIn = parseFloat(document.getElementById('alc-trade-in').value) || 0; var interestRate = parseFloat(document.getElementById('alc-interest').value) || 0; var months = parseInt(document.getElementById('alc-term').value) || 60; // 2. Logic Implementation // Calculate Sales Tax Amount (Assuming tax is on the full vehicle price, common in many states) var taxAmount = price * (taxRate / 100); var totalPrice = price + taxAmount; // Calculate Amount Financed var loanAmount = totalPrice – downPayment – tradeIn; // Handle edge case where down payment + trade in > price if (loanAmount < 0) { loanAmount = 0; } var monthlyPayment = 0; var totalInterest = 0; var totalCost = 0; // Calculate Monthly Payment if (interestRate === 0) { monthlyPayment = loanAmount / months; totalInterest = 0; } else { var monthlyRate = (interestRate / 100) / 12; // Amortization Formula: P * (r(1+r)^n) / ((1+r)^n – 1) var mathFactor = Math.pow(1 + monthlyRate, months); monthlyPayment = loanAmount * ((monthlyRate * mathFactor) / (mathFactor – 1)); totalCost = monthlyPayment * months; totalInterest = totalCost – loanAmount; } // 3. Update UI document.getElementById('alc-monthly-payment').innerHTML = '$' + monthlyPayment.toLocaleString(undefined, {minimumFractionDigits: 2, maximumFractionDigits: 2}); document.getElementById('alc-total-loan').innerHTML = '$' + loanAmount.toLocaleString(undefined, {minimumFractionDigits: 2, maximumFractionDigits: 2}); document.getElementById('alc-total-interest').innerHTML = '$' + totalInterest.toLocaleString(undefined, {minimumFractionDigits: 2, maximumFractionDigits: 2}); // Show Results document.getElementById('alc-results-area').style.display = 'block'; }

Understanding Your Auto Loan Financing

Purchasing a vehicle is often the second largest financial decision a household makes, right after buying a home. Our Auto Loan Calculator is designed to help you navigate the complexities of dealership financing, trade-in values, and interest rates to reveal the true cost of your next car.

Unlike simple loan calculators, this tool accounts for Sales Tax and Trade-In Equity, two critical factors that significantly impact your final financed amount and monthly budget.

How Interest Rates Impact Your Buying Power

Your Annual Percentage Rate (APR) is the cost of borrowing money. Even a small difference in APR can lead to thousands of dollars in extra costs over the life of a loan. Factors affecting your rate include:

• Credit Score: Buyers with scores above 720 typically qualify for "prime" rates.
• New vs. Used: New cars often come with manufacturer incentives (like 0% or 1.9% APR), while used car loans generally carry higher rates.
• Loan Term: Longer terms (72 or 84 months) usually have higher interest rates than shorter terms (36 or 48 months).

The "Out-the-Door" Price Formula

Many buyers focus solely on the sticker price, but the "Out-the-Door" (OTD) price is what you actually finance. Our calculator estimates this by adding sales tax to the vehicle price before subtracting your down payment and trade-in credit.

Formula: (Vehicle Price + Sales Tax) – Down Payment – Trade-In = Amount Financed.

The 20/4/10 Rule for Car Buying

Financial experts often recommend the 20/4/10 rule to ensure your car purchase doesn't derail your financial goals:

• 20% Down: Aim to put at least 20% down to avoid "gap" situations where you owe more than the car is worth.
• 4 Years: Limit your loan term to 4 years (48 months) to minimize interest paid.
• 10% of Income: Your total monthly transportation costs (payment, insurance, gas) should not exceed 10% of your monthly gross income.

Negative Equity and Trade-Ins

If your trade-in value is less than what you owe on your current vehicle, you have "negative equity." If you roll this debt into your new loan, your monthly payment will increase significantly. Always check your trade-in's current market value before visiting the dealership to ensure you get a fair credit toward your new purchase.