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EZ Auto Loan Calculator

Independent auto loan estimates for the United States. Not a bank or dealer offer.

Payment, totals, and finance charge

Auto Loan Interest Calculator

This Auto Loan Interest Calculator shows the monthly payment, the total of those payments, and the estimated interest if you keep the loan to the last month. Enter the vehicle price, APR, term, down payment, and trade-in. The interest — the finance charge — is then stated as a percent of the total of payments.

Loan details

Enter the vehicle price, APR, and term. The down payment and trade-in can stay at 0. Then choose Estimate total cost.

How to calculate interest on an auto loan

First the calculator finds the amount financed: price minus down payment minus trade-in. Then it estimates a fixed monthly payment with the same amortizing formula as the Auto Loan Calculator. The total of payments is that installment multiplied by the term. Interest — the finance charge on this page — is the total of payments minus the amount financed.

That interest is not a second invoice. It is the part of the payments that never reduces principal. After those two totals exist, the calculator states interest as a percent of the total of payments, in a full sentence on the result.

Why a longer term can look cheaper and cost more

A move from 60 months to 72 or 84 months usually cuts the monthly payment. The finance charge often goes up because the balance stays outstanding longer. The term table on the result uses your price and APR. Paying the loan off early changes the interest; this page assumes you make every scheduled payment.

Examples you can run on this page

  1. A $32,000 vehicle, $4,000 down, 6.49 percent APR, and 60 months finances $28,000. The payment is $547.72. The total of payments is $32,863.26. Estimated interest is $4,863.26, which is 14.8 percent of the total of payments.
  2. An $18,500 vehicle at 0 percent APR for 36 months has a payment of $513.89. The total of payments equals the amount financed, so interest is $0.00 and the interest share is 0.0 percent.
  3. A $42,000 vehicle, $6,000 down, a $2,500 trade-in, 9.25 percent APR, and 72 months finances $33,500. The payment is $608.02. The total of payments is $43,777.47. Estimated interest is $10,277.47.

Interest and finance-charge questions

How do you calculate interest on an auto loan?

Estimate the payment, multiply by the term, and subtract the amount financed. The remainder is the estimated finance charge if you keep the loan to the end.

Is interest added on top of the monthly payment?

No. Interest is already inside the payment. The interest line only separates that portion from principal.

Does this include sales tax or dealer fees?

No. Those items change the amount financed only if you add them to the price yourself.

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