Car Loan Calculator
Work out your real monthly car payment — including sales tax, trade-in value and down payment — before you set foot in the dealership.
What actually determines your car payment
The amount you finance is the vehicle price plus sales tax, minus your down payment and trade-in. That balance is amortized over the term at your interest rate — the same formula as any fixed loan. Two levers matter most: the amount financed (negotiate the price, bring a bigger down payment) and the term length.
The long-term trap
Dealers often pitch 72- or 84-month terms because they make expensive cars feel affordable. But longer terms mean more total interest and more time "underwater" — owing more than the car is worth as it depreciates. Compare a 60- vs 84-month term above: the payment drops, but watch the "Total interest" figure climb.
Rules of thumb
- 20/4/10: 20% down, no more than a 4-year term, total vehicle costs under 10% of gross income.
- Get pre-approved by your bank or credit union first — it gives you a rate to beat and strengthens your negotiating position.
- Negotiate the vehicle price, not the monthly payment. A "lower payment" often hides a longer, costlier term.