Auto Loan Calculator
Before you sign at the dealership, see what the car really costs per month — and in total — once financing, down payment and interest are included.
Why the sticker price is only the beginning
A $32,000 car with $4,000 down at 7.5% over 60 months costs $561/month — and about $37,700 in total once interest is included. Stretch the same loan to 84 months and the payment drops to $429, but total interest grows by roughly $2,400 and you're still making payments on a four-year-old car. Dealership payment-focused selling exploits exactly this: the monthly number can always be lowered by stretching the term, while the true cost quietly rises.
The math behind the payment is the standard amortization formula — identical to mortgages and personal loans:
Where P is the amount financed (price minus down payment), r is the monthly APR, and n is the loan length in months.
Three things to check before financing a car
- Get a pre-approval first. Walk in with a bank or credit-union rate in hand and make the dealership beat it, not set it.
- Keep the term at 60 months or less. Beyond that, depreciation outruns your payoff and you can end up "upside down" — owing more than the car is worth if it's totaled or sold.
- Put 10–20% down if possible. It directly shrinks the financed amount, which is where every dollar of interest comes from.
Also remember that taxes, registration, and fees are usually rolled into the financed amount — if you want the loan to cover those, add them to the vehicle price before calculating.
Frequently asked questions
How is a car loan payment calculated?
Same amortization formula as any installment loan, applied to the amount financed (price minus down payment) over the number of months.
Is 0% dealer financing worth it?
Sometimes dealers offer 0% APR instead of a cash rebate. Compare both with this calculator — taking the rebate and financing at your bank's rate is often the cheaper total-cost path.
Should I pay off my auto loan early?
Usually fine if there's no prepayment penalty, and it saves the remaining interest. But if the rate is low (under ~5%) and you have higher-interest debt, clear that first.