Auto Loan Calculator
Most car calculators use the sticker price. Real deals add sales tax and dealer fees, and often roll in what you still owe on your old car. all of it borrowed. This shows the real number, and the month you finally stop owing more than the car is worth.
Your monthly payment
-
- Price on the window
- $0
- Out-the-door price
- $0
- What you actually borrow
- $0
- Sales tax
- $0
- Old debt rolled in
- $0
- Total interest
- $0
Where the money goes
Each block is sized by its share, so you can see whether price on the window or out-the-door price is the bigger part without reading a single number.
Move it and watch
-
at {v} for price of the car
And what you can change
Why your own figure may differ
What the loan length really costs
A longer loan always looks kinder each month. Look at the last column before you agree to one.
| Length | Monthly payment | Total paid | Total interest |
|---|
Car loans: real examples
Three situations that cost real money. Click any card to load it.
- The sticker-price surprise
$35,000 car, $5,000 down
6% sales tax and $800 in dealer fees, over 60 months at 7%.
You borrow $32,900, not the $30,000 you expected - because $2,900 of tax and fees gets financed too.
Load this scenario in the calculator → - Old debt coming along
Owing $12,000 on a car worth $8,000
Trading it in against a $30,000 replacement.
$4,000 of old debt rolls into the new loan. You start the new car already behind, and stay upside down far longer.
Load this scenario in the calculator → - The long-loan trap
$30,000 at 7% - 36 months or 72?
The dealer offers to lower your payment.
$926 versus $511 a month. but $3,347 versus $6,826 in interest. The lower payment costs you roughly double.
Load this scenario in the calculator →
Common questions about car loans
Why is my payment higher than I worked out?
Because you almost certainly budgeted from the sticker price. Sales tax and dealer fees get added on and then borrowed along with everything else, so the amount you actually finance is bigger than the price of the car. This calculator shows both figures, so there is no surprise at the desk.
What does it mean to be upside down?
It means you owe more than the car is worth. Cars lose value fastest in their first couple of years, usually faster than a long loan pays down. Until the two lines cross you cannot sell the car without writing a cheque to cover the difference. This tool shows you the exact month that stops being true.
I still owe money on my old car. What happens?
If you owe more than the dealer gives you for it, the difference does not disappear - it usually gets added to the new loan. That is called rolling over negative equity, and it means starting the new car already behind. Put both numbers in and you will see exactly how much old debt is coming with you.
Is a longer loan a good idea?
It lowers the monthly payment, which is why dealers offer it. But you pay far more interest and you stay upside down for much longer. On $30,000 at 7%, stretching from 36 to 72 months drops the payment by about $415 a month - and roughly doubles the interest. The comparison table shows this for your own numbers.
Is sales tax charged on the full price?
It depends where you live. Many states charge tax only on the price after your trade-in is deducted, which can save a meaningful amount. Others tax the full price. There is a switch for this - if you are not sure which applies, your dealer or state motor vehicle site will know.
What is the 20/4/10 guideline?
A widely repeated rule of thumb: put at least 20% down, borrow for no more than 4 years, and keep all your transport costs under 10% of your monthly income. It is guidance rather than law, and plenty of sensible people break it. The tool shows how your deal measures up so you can decide knowingly.