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Finance

Auto Loan Calculator

Estimate your monthly car payment, loan amount, total interest and the full cost of a vehicle, including down payment, trade-in, sales tax and fees.

Free ยท no sign-up Runs in your browser
Vehicle and loan
Trade-in (optional)
Tax and fees (optional)
Sales tax is charged on the price minus the trade-in value and is added to the loan. Unchecked fees are paid upfront.

How to use the auto loan calculator

Enter the vehicle price, the annual interest rate and choose a loan term from 24 to 84 months, or pick Other to type any term up to 120 months. Then add whatever applies to your deal:

  • Down payment: cash you pay at signing.
  • Trade-in value and amount owed on trade-in: what the dealer gives you for your old car and what you still owe on it.
  • Sales tax (%) and fees such as title, registration and dealer documentation charges.

Tick Include fees in loan to finance the fees, or untick it to pay them upfront. Press Calculate to see the monthly payment, the loan amount, total interest, the total cost of the car and a yearly amortization schedule.

How the loan amount is worked out

The calculator assumes that sales tax is charged on the price minus the trade-in value, which is how many US states tax a trade-in deal, and that the tax is added to the loan. Your net trade-in is its value minus what you owe. If you owe more than the car is worth, the difference (negative equity) is added to the new loan.

Loan amount = price + sales tax + financed fees − down payment − net trade-in

The monthly payment then follows the standard annuity formula M = P × r / (1 − (1 + r)^−n), where P is the loan amount, r is the annual rate divided by 12 and n is the number of months. At 0% financing the payment is simply P / n.

Worked example

A car costs 30,000. You put 3,000 down and trade in a car worth 5,000 that still has 2,000 owing. Sales tax is 7% and fees of 500 are financed, at 6% for 60 months.

  • Sales tax: (30,000 − 5,000) × 7% = 1,750
  • Loan amount: 30,000 + 1,750 + 500 − 3,000 − 3,000 = 26,250
  • Monthly payment: 507.49
  • Total interest: 4,199.16
  • Total cost of the car: 30,000 + 1,750 + 500 + 4,199.16 = 36,449.16

Good to know

  • The total cost counts the price, tax, fees and interest. It equals everything you hand over: the down payment, your trade-in equity, any upfront fees and all loan payments.
  • Tax rules differ by state and country. Some places tax the full price, ignore the trade-in or do not let you finance tax, so check local rules.
  • Results are estimates. A dealer's quote may include extras such as warranties, gap insurance or different rounding.
  • A longer term lowers the payment but raises the total interest.

Frequently asked questions

Is sales tax calculated on the full price?

This calculator applies sales tax to the vehicle price minus the trade-in value, a common rule in many US states. If your area taxes the full price, you can enter a slightly higher tax rate or add the extra tax to the fees field to match your deal.

What happens if I owe more on my trade-in than it is worth?

That gap is called negative equity. The calculator adds it to the new loan, so you borrow more and pay interest on it. Paying it off in cash or waiting until the old loan is smaller keeps the new loan lower.

Should I include fees in the loan?

Financing fees keeps more cash in your pocket today, but you pay interest on them for the whole term. Paying them upfront lowers both the loan amount and the total interest.

Does the calculator handle 0% financing?

Yes. Enter 0 as the interest rate and the monthly payment is the loan amount divided by the number of months, with no interest at all.