Auto loan calculator
Enter the price, what you're putting down, your rate and the term to see the monthly payment, the interest over the loan and the all-in cost.
Your monthly payment
$615.97
$30,740.00 financed, $6,217.99 of interest over 60 months
How to use it
- Enter the negotiated price of the vehicle, not the sticker price.
- Enter your down payment and trade-in value. Both reduce the amount financed, and the trade-in usually reduces the sales tax too.
- Enter your state's sales tax rate and any fees the dealer is rolling into the loan.
- Enter the APR you've been offered and pick the term. Read the monthly payment, then compare the interest line across terms before you sign.
Worked example
A car negotiated to $32,000 with $4,000 down, no trade-in, 7% sales tax and $500 of fees, financed at 7.5% for 60 months.
Sales tax: $32,000 × 7% = $2,240. Amount financed: $32,000 + $2,240 + $500 − $4,000 = $30,740. Monthly payment: $615.97. Interest over five years: $6,217.99, and the car costs $40,957.99 all in.
The same loan over 72 months drops the payment to $531.50 but the interest rises to $7,527.84.
How this is calculated
The amount financed is the price plus sales tax and any fees you roll in, minus your down payment and trade-in. Sales tax is applied to the price after the trade-in, which is how most states do it. The monthly payment is the standard level payment for that amount, rate and term, the same formula the dealer's finance office uses. Interest is then added up month by month with cent rounding, the way the lender books it, so the total is exact rather than payment times months. The all-in figure is every payment plus the cash and trade-in you put down: what the car actually costs you.
sales tax = (price − trade-in) × tax rate
amount financed = price + sales tax + fees − down payment − trade-in
monthly payment = amount financed × r × (1 + r)ⁿ ÷ ((1 + r)ⁿ − 1), where r is the APR ÷ 12 and n is the number of months
total interest = the sum of each month’s interest on the remaining balance, rounded to the cent
all-in cost = total of payments + down payment + trade-in
Rates, sources and limits
Estimates for a simple-interest loan. Your lender's amount financed, fees and rounding may differ slightly. Not financial advice.
Last reviewed 23 Sep 2026 by the CalcRabbit team. Estimates only, not financial, tax or medical advice.
Frequently asked questions
Should I take the longer term for the lower payment?
Only if the lower payment is what makes the car affordable at all. Every extra year adds interest and keeps you underwater on the loan longer, since cars lose value faster than a long loan pays down. Many lenders also charge a higher rate above 60 months. Compare the interest line, not just the payment.
Does the trade-in really reduce sales tax?
In most states, yes: tax is charged on the price minus the trade-in allowance. A handful of states, including California, tax the full price. If yours does, set the trade-in to 0, enter the tax on the full price, and subtract the trade-in from the down payment instead.
What's the difference between the rate and the APR?
For a car loan they're usually the same number, because dealer loans rarely carry separate origination fees. If a lender quotes a rate and fees separately, use the APR calculator to fold them together before comparing.
Can I pay it off early?
Most simple-interest auto loans can be paid off early with no penalty, and extra payments go straight to principal. The loan payoff calculator shows what an extra $50 or $100 a month saves.
Is the payment quoted here what the dealer will quote?
The formula is identical. Differences come from the exact amount financed, which is where add-ons like extended warranties and GAP insurance get folded in. Ask for the amount financed on the buyer's order and enter that as the price with tax and fees at zero to check their number.