Auto Loan Calculator
Calculate your monthly car payment with down payment, trade-in, sales tax, and interest. See total cost and interest over the loan term.
Monthly Payment
$644.08
Loan Amount
$32,450
incl. $2,450 sales tax
Total Interest
$6,195
Total Cost
$43,645
* Sales tax treatment of trade-ins varies by state. Most states reduce the taxable amount by the trade-in value; a few tax the full vehicle price. Verify with your state's DMV or a local dealer.
Frequently Asked Questions
Does this calculator include sales tax?
Yes. This calculator estimates sales tax based on the taxable vehicle price and the sales tax rate you enter. Sales tax is added to the purchase price before computing your financed amount, so your loan principal and monthly payment reflect the full out-of-pocket cost of financing.
Is sales tax applied before or after the trade-in?
In most U.S. states, sales tax is calculated on the vehicle price minus the trade-in value — meaning your trade-in reduces the taxable amount. This calculator follows that common approach, but tax treatment varies by state. A few states tax the full vehicle price regardless of trade-in. Check your state's DMV or a local dealer for the exact rule in your area.
How is my monthly car payment calculated?
The monthly payment uses the standard amortization formula: P × r × (1 + r)^n / ((1 + r)^n − 1), where P is the loan principal, r is the monthly interest rate (APR ÷ 12), and n is the loan term in months. If your APR is 0%, the payment is simply P ÷ n. Each payment covers accrued interest first; the remainder reduces the principal balance.