Estimate your monthly car payment, total interest paid, and the true cost of your vehicle — including taxes and fees.
| Period | Payment | Principal | Interest | Balance |
|---|---|---|---|---|
| Calculate your loan to see the schedule | ||||
Buying a car is one of the largest purchases most Americans make, yet many buyers focus only on the monthly payment without fully understanding the total cost of financing. An auto loan calculator helps you see the full picture — including how much of your payment goes toward interest versus principal each month.
Auto loans use simple interest amortization. Your monthly payment is fixed, but the split between principal and interest changes each month. Early in the loan, a larger share goes to interest; as the balance decreases, more of each payment chips away at principal. This is why paying even a little extra per month can dramatically reduce total interest paid.
Most buyers remember to factor in the down payment and loan term but forget that sales tax is often rolled into the financed amount. In a state with 8.5% sales tax, a $32,000 vehicle carries $2,720 in tax — money you pay interest on for the entire loan term if financed. This calculator adds sales tax to the loan amount automatically so you see the full picture.
A longer loan term (72 or 84 months) lowers your monthly payment, making a more expensive car feel affordable. But longer terms mean paying significantly more in total interest, and you risk becoming "underwater" — owing more than the car is worth — because vehicles depreciate faster than long-term loan balances decrease. For most buyers, a 48–60 month term strikes the best balance.
Your credit score is the single biggest factor in the rate you receive. Borrowers with excellent credit (720+) can often secure rates under 5%, while subprime borrowers may face rates above 15%. Always get pre-approved by your bank or credit union before visiting a dealership — this gives you negotiating power and a baseline rate to compare against dealer financing. Credit unions typically offer lower rates than banks or manufacturer financing.
Every dollar you put down or receive as a trade-in credit reduces your loan principal, which lowers both your monthly payment and total interest. A 20% down payment is a common financial guideline — it helps prevent going underwater on the loan and keeps payments manageable. If your trade-in has negative equity (you owe more than it's worth), that balance is typically rolled into your new loan, increasing your financing costs.