🚗 Auto Loan Calculator

Use this auto loan calculator to estimate your monthly car payment, total interest, and overall cost of financing a vehicle. Enter the price, down payment, trade-in value, interest rate, term, taxes, and fees to see how different scenarios fit your budget.

Auto loan results

Enter your vehicle price, loan details, and any down payment or trade-in above, then select Calculate Auto Loan to see your estimated monthly payment, total interest, and overall cost of financing.

Auto loan amortization schedule

After you calculate your auto loan, this section will show a month-by-month breakdown of each payment, including how much goes to interest and how much reduces the principal balance.

Auto loan calculator inputs and key terms

Understanding each input makes it easier to compare offers from dealers, banks, and credit unions and to see the real cost of a car loan.

• Vehicle price: The negotiated purchase price of the car before taxes, fees, and trade-in credits are applied.
• Down payment: The amount you pay upfront in cash or from a separate source. A larger down payment reduces how much you need to finance and can lower your monthly payment and interest costs.
• Trade-in value: The amount the dealer gives you for your current vehicle. In many places, trade-in value can reduce the taxable amount of the new car purchase.
• APR (annual percentage rate): The yearly interest rate on the loan, including certain lender charges. It is usually higher than the simple interest rate and provides a better apples-to-apples comparison between loan offers.
• Loan term (years): How long you will take to repay the loan if you make only the scheduled monthly payments. Longer terms lower the monthly payment but usually increase total interest.
• Sales tax rate (%): The tax rate applied to the vehicle purchase in your state or region. This calculator uses a simple estimate by taxing the price minus trade-in, then adding that amount to the loan if not covered by the down payment.
• Additional fees: Extra costs such as documentation fees, title and registration, or add-on products that are rolled into the loan balance.
• Amount financed: The portion of the car’s cost you’re borrowing after taking into account down payment, trade-in value, taxes, and fees.
• Monthly payment: The regular payment you’ll owe each month to repay principal and interest over the term at the given APR.
• Total interest and total cost: The sum of all interest charges over the life of the loan and the combined cost of down payment, taxes, fees, and monthly payments.

Formulas used in the Auto Loan Calculator

This calculator uses standard fixed-rate loan formulas to estimate your monthly payment and to build an amortization schedule for your auto loan.

Calculating the amount financed

For this tool, the amount financed is estimated as:
Taxable amount = max(Vehicle price − Trade-in value, 0)
Sales tax = Taxable amount × Sales tax rate
Amount financed = Taxable amount + Sales tax + Fees − Down payment
If the result is negative, the financed amount is set to zero.

Monthly payment formula

Let:
P = amount financed
r = annual interest rate (APR) as a decimal (for example, 0.069 for 6.9%)
i = monthly interest rate = r ÷ 12
n = total number of payments = years × 12
When the interest rate is greater than zero, the standard fixed payment per month PMT is:
PMT = P × i ÷ (1 − (1 + i)−n)
If the APR is exactly 0%, the formula simplifies to:
PMT = P ÷ n

Amortization step for each month

Starting from the current balance B:
Interest = B × i
Principal = Payment − Interest
New balance = B − Principal
The calculator repeats this process for each month until the balance reaches zero, creating the month-by-month schedule you see in the table.

Actual auto loans may include additional fees, different compounding conventions, or prepayment rules. Always review your loan contract to understand exactly how your payments will be calculated.

Auto Loan Calculator FAQs

• How accurate is this auto loan calculator?
  This calculator uses standard fixed-rate loan formulas to estimate payments, interest, and totals. It gives a solid ballpark figure for comparing options and planning a budget. However, actual offers can differ based on fees, exact tax handling, compounding, and dealer or lender policies. Always compare the results to the official loan disclosure before making a decision.
• How much should I put down on a car?
  A larger down payment reduces how much you need to finance and can lower your monthly payment and total interest. Many buyers aim for 10–20% of the vehicle price, but the right amount depends on your savings, other debts, credit score, and how long you plan to keep the vehicle. Use the calculator to test different down payment scenarios.
• Should I choose a shorter or longer loan term?
  Shorter terms usually mean higher monthly payments but less total interest, while longer terms lower the monthly payment but increase total interest paid. If you can comfortably afford a higher payment, a shorter term can save money over time. If cash flow is tight, a longer term may be more manageable, but you may pay significantly more in interest.
• How do trade-in value and taxes affect my auto loan?
  In many regions, the trade-in value reduces the taxable portion of the purchase, which can lower sales tax and the amount you need to finance. This calculator uses a simple estimate by taxing the purchase price minus trade-in. Your state’s rules may differ, so check local regulations or ask the dealer how taxes are applied in your area.
• Is it better to finance through the dealer or a bank/credit union?
  Dealer financing can be convenient and sometimes offers promotional rates, but it is not always the cheapest option. Banks and credit unions often provide competitive rates, especially if you have a strong relationship or good credit. It’s usually smart to get pre-approved from an outside lender and then compare that offer to the dealer’s financing using a calculator like this one.
• Can I pay off my auto loan early without penalty?
  Some auto loans allow you to pay extra or pay off the balance early with no penalty, while others include prepayment fees or restrictions. Check your loan agreement or ask the lender before making extra payments. If early payoff is allowed, using additional payments can reduce total interest and shorten the life of the loan.