Auto loan calculator
Estimate your monthly car payment, how much interest you will pay, and what the car really costs once sales tax and financing are added.
How your car payment is calculated
Sales tax is added to the price after any trade-in credit. Your down payment and trade-in are subtracted, and the rest is the amount financed. The loan is then repaid in equal monthly payments that cover interest and principal.
Example
A $35,000 car with 7% sales tax adds $2,450 of tax. With $5,000 down, you finance $32,450. At 7.5% APR for 60 months the payment is $650.23 a month and you pay $6,563.89 in interest. Stretching the loan to 72 months lowers the payment to $561.06, but the interest rises to $7,946.62.
Sales tax and trade-ins
Most states charge sales tax only on the difference between the new car's price and your trade-in, which can save you hundreds of dollars. Not every state does this: California, for example, taxes the full price. Dealer documentation fees, title and registration costs are extra and vary by state.
Frequently asked questions
What is a good APR for a car loan?
It depends mainly on your credit score, whether the car is new or used, and the loan term. Borrowers with excellent credit often get the lowest rates, and used-car loans usually cost more. Compare offers from banks and credit unions before visiting the dealer.
How much should I put down?
A common guide is 20% on a new car and 10% on a used one. A bigger down payment lowers your payment and interest and helps you avoid owing more than the car is worth.
Estimates for guidance only. Fees, rebates and dealer incentives are not included.
Last checked and updated: October 2026