Auto Loan Calculator

Finance

Last updated: July 11, 2026

Calculate your monthly car payment, total interest cost, and see a detailed amortization schedule for your auto loan. Factor in your down payment and trade-in value to get the most accurate estimate.

Vehicle Price ($)

Down Payment ($)

Trade-in Value ($)

Interest Rate (APR %)

Loan Term (months)

How to Use This Calculator

Enter the Vehicle Price (sticker price or negotiated price).
Input your Down Payment and Trade-in Value to reduce the loan principal.
Set the Interest Rate (APR) offered by your lender or dealer financing.
Choose a Loan Term in months (24, 36, 48, 60, 72, or 84).
Click Calculate to see your monthly payment, total interest, and amortization breakdown.

Formula

M = P × [r(1+r)ⁿ] / [(1+r)ⁿ − 1]

Where M = monthly payment, P = principal (vehicle price − down payment − trade-in value), r = monthly interest rate (APR / 12), and n = total number of months. This is the standard amortization formula used by auto lenders.

Examples

New Car Purchase: $35,000 vehicle, $5,000 down, $3,000 trade-in. Loan of $27,000 at 6.5% for 60 months = $527.03/month. Total interest: $4,622.

36 vs 72 Months: A $25,000 loan at 7%: 36 months = $772/mo ($2,784 total interest), 72 months = $427/mo ($5,767 total interest). The shorter term saves $2,983.

Bigger Down Payment: On a $40,000 car at 6% for 60 months, putting $10,000 down instead of $5,000 reduces the monthly payment by $95 and saves $1,405 in total interest.

Frequently Asked Questions

How is auto loan interest calculated?

Auto loan interest uses standard amortization. Each month, your interest charge is the remaining balance multiplied by the monthly rate (APR ÷ 12). The rest of your payment goes toward the principal. Early payments are interest-heavy; later payments reduce principal faster.

Should I put more money down on a car?

Yes, a larger down payment reduces your loan amount, lowers your monthly payment, decreases total interest, and helps you avoid being "underwater" (owing more than the car is worth). A 20% down payment is generally recommended for new cars.

Is a 72-month auto loan a bad idea?

Longer terms lower monthly payments but significantly increase total interest paid. A 72-month loan also puts you at risk of owing more than the car's value as it depreciates. Financial experts typically recommend keeping auto loans at 60 months or less.

Does my credit score affect the interest rate?

Absolutely. Borrowers with excellent credit (750+) may qualify for rates under 5%, while subprime borrowers (below 600) may face rates of 10–15% or higher. Improving your credit before applying can save thousands over the life of the loan.