Auto Loan Calculator
Estimate the amount financed, monthly payment, interest, and the effect of extra payments.
How to calculate an auto loan payment
The calculator first estimates sales tax under the selected rule. It then combines the vehicle price, debt still owed on a trade-in, sales tax, and fees; and subtracts the down payment, trade-in value, and rebate. The result is the amount financed.
M = P × r(1 + r)n ÷ [(1 + r)n − 1]
P is the amount financed, r is APR divided by 12, and n is the number of monthly payments. At 0% APR, payment equals P ÷ n.
Trade-in equity and negative equity
Net trade equity equals trade-in value minus the amount still owed. Positive equity reduces the new loan. Negative equity increases it because the unpaid balance is rolled into the financing. A lender may restrict how much negative equity can be financed even when the arithmetic produces a payment.
Sales-tax treatment
Tax rules differ by jurisdiction. Some locations tax the full vehicle price; others allow the trade-in value, or both the trade-in and rebate, to reduce the taxable amount. Choose the rule that matches your quote and verify the result with the dealer or local revenue authority.
Example
For a $35,000 vehicle, $5,000 down, 7% tax on the price after trade-in, $800 in fees, 6.5% APR, and a 60-month term, the calculator combines every financed cost before applying the standard amortization formula. Change the trade-in, rebate, or extra payment to see its effect immediately.
What this estimate excludes
The result does not include insurance, fuel, maintenance, repairs, parking, optional service contracts, late fees, or lender-specific requirements unless you enter them in fees. It assumes a fixed APR and no prepayment penalty. Compare the calculated amount financed with the contract before signing.
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