AutoLoan Pro

Auto Loan Calculator

Get the real monthly cost of a new car — including trade-in credit and state sales tax.

Vehicle price

Sales tax (state)

Down payment

Trade-in value

Loan term (months)

APR

What you entered

Vehicle price: $32,000Down + trade-in: $4,000APR: 6.9%Term: 60 months

1
Sales tax on the taxable amount
tax = max(0, $32,000.00 − $0.00) × 7%= $2,240.00
2
Loan principal after tax, down payment, and trade-in
$32,000.00 + $2,240.00 − $4,000.00 − $0.00= $30,240.00
3
Convert APR to a monthly rate
r = 6.9% ÷ 12= 0.5750%
4
Apply the amortizing-loan formula
M = P × [r(1+r)ⁿ] / [(1+r)ⁿ − 1]= $597.36/mo
5
Total interest over the loan term
$597.36 × 60 − $30,240.00 principal= $5,601.75

Result

Monthly payment: $597.36

Financing $30,240 at 6.9% APR over 60 months costs $5,602 in interest — total cost of ownership comes to $39,842 including your down payment and trade-in.

Monthly car payment by price and loan term

Each row takes the vehicle price, adds 7% sales tax, subtracts a 10% down payment with no trade-in, and runs the balance at 7.5% APR through the amortizing-loan formula. The loan column is the amount actually financed after tax and down payment.

Vehicle price	Amount financed	36 months	48 months	60 months	72 months
$15,000	$14,550	$452.60	$351.80	$291.55	$251.57
$20,000	$19,400	$603.46	$469.07	$388.74	$335.43
$25,000	$24,250	$754.33	$586.34	$485.92	$419.29
$30,000	$29,100	$905.19	$703.61	$583.10	$503.14
$35,000	$33,950	$1,056.06	$820.87	$680.29	$587.00
$40,000	$38,800	$1,206.92	$938.14	$777.47	$670.86
$50,000	$48,500	$1,508.65	$1,172.68	$971.84	$838.57

Notice the amount financed exceeds the price minus the down payment, because sales tax is financed too. Stretching a $30,000 car from 36 to 72 months cuts the payment by $402 a month and raises total interest from about $3,487 to $7,126. Longer terms also keep you in negative equity for longer, since the car depreciates faster than the balance falls. Sales tax rates, dealer fees and your own APR all vary - your rate depends on credit score and is what moves these numbers most, so run your own figures above.

The total cost trap

A 72-month loan looks cheap monthly but you'll pay thousands more in interest, and you'll likely be 'upside down' (owing more than the car is worth) for years.

New vs used car loan math

Used cars have lower sticker prices but higher interest rates (typically 1–3% more). A $25,000 used car at 8% for 60 months costs $507/month ($5,416 interest). A $35,000 new car at 5% for 60 months costs $660/month ($4,619 interest). The new car costs more monthly but less in interest — run both scenarios.

Frequently asked questions

What is a good interest rate for a car loan?

As of 2024–2025, good rates for new cars are 5–7% APR with good credit (700+). Used cars are typically 1–2% higher. Excellent credit (750+) can get below 5%. Rates above 10% usually mean subprime lending — consider improving your credit score before buying.

How much car can I afford?

A common guideline: your total car costs (payment + insurance + gas + maintenance) should be under 15–20% of your take-home pay. On $4,000/month take-home, that's $600–800 total. Keep the loan term at 60 months or less to avoid being underwater.

Should I get a 60 or 72 month car loan?

A 60-month loan has higher monthly payments but you pay significantly less interest and build equity faster. A 72-month loan lowers the monthly payment but costs thousands more in interest, and you'll owe more than the car is worth for most of the loan. On a $30,000 loan at 6%, the 72-month option costs about $2,000 more in total interest.