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Auto Loan Calculator

Calculate your car loan's monthly payment, amount financed, sales tax, total interest, and total cost — or find the auto price you can afford from a target payment.

$
months
%

Annual percentage rate (APR).

$

Manufacturer rebate — reduces the amount financed.

$
$
$

Loan balance still owed on your trade-in.

%
$

Most states tax price minus trade-in. Uncheck for CA, DC, HI, KY, MD, MI, MT, VA.

Monthly Payment

$693.04

Loan Amount
$35,000.00
Sales Tax
$2,800.00
Upfront Payment
$8,100.00
Total of Loan Payments
$41,582.52
Total Loan Interest
$6,582.52
Total Cost
$49,682.52

Principal vs interest

Principal 84%, Interest 16%
  • Principal84%
  • Interest16%

Amortization schedule

PeriodInterestPrincipalBalance
Year 1$2,258.07$6,058.43$28,941.57
Year 2$1,820.11$6,496.39$22,445.18
Year 3$1,350.49$6,966.02$15,479.16
Year 4$846.91$7,469.59$8,009.57
Year 5$306.93$8,009.57$0.00
Monthly Payment$693.04View results

Work out the real cost of a car loan. In the Total Price tab, enter the auto price to get your monthly payment; in the Monthly Payment tab, enter a target payment to find the price you can afford. Both account for down payment, trade-in, sales tax, and fees.

Formula

First the amount financed is determined, then it's amortized into equal monthly payments. With trade-in tax credit (most states):

Sales tax      = tax% × (auto price − trade-in value)
Amount financed = auto price − down payment − trade-in + amount owed on trade-in
                  − cash incentives  (+ tax + fees, if rolled into the loan)
Monthly payment = financed × r / (1 − (1 + r)⁻ⁿ)     r = APR ÷ 12,  n = months

The Monthly Payment tab inverts this: it converts your target payment back to an amount financed, then solves for the auto price.

Rolling taxes and fees into the loan reduces your upfront cash but means you pay interest on them — paying upfront is cheaper overall.

Examples

$40,000 car, $5,000 down, 60 months at 7%

With 7% sales tax and $300 in fees paid upfront and no trade-in, you finance $35,000. That's a monthly payment of about $693.04, around $6,583 in total interest, and roughly $8,100 due upfront (down payment + tax + fees).

Working backward from a $600 payment

Switch to the Monthly Payment tab: a $600 payment over 60 months at 7%, with the same $5,000 down and $300 fees, corresponds to an auto price of about $35,300.

Frequently asked questions

How is a car loan's monthly payment calculated?
The amount you finance (price − down payment − trade-in + any balance owed on the trade-in, plus tax and fees if you roll them in) is amortized over the term using M = P · r / (1 − (1 + r)⁻ⁿ), where r is the monthly rate (APR ÷ 12) and n is the number of months.
How does a trade-in lower my sales tax?
In most states you only pay sales tax on the price after the trade-in is deducted, so a trade-in reduces both the amount financed and the tax. Eight states (CA, DC, HI, KY, MD, MI, MT, VA) tax the full price — uncheck "Trade-in reduces taxable amount" for those.
Should I include taxes and fees in the loan?
Rolling taxes and fees into the loan lowers your upfront cash but increases the amount financed, so you pay interest on them. Paying them upfront costs more now but less overall.
What does the Monthly Payment tab do?
It works backward: enter the monthly payment you can afford along with the term, rate, and your trade-in/down payment, and it returns the auto price that fits that budget.
Does a longer term make a car cheaper?
Only the monthly payment — not the car. A longer term lowers each payment but charges interest for more months, so you pay more total interest.

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