Auto loans are typically secured loans that charge simple interest, interest calculated on your loan balance, over two to seven years. Your auto loan interest rate is determined by your credit score, loan term and amount, along with the value of the car itself. While many buyers shop for a car loan at the same time they’re shopping for a car, a better way is to compare annual percentage rates (APRs) across multiple lenders to make sure you’re getting a competitive rate. If the dealer can beat it, you’ll know you’re getting a fair offer.