Auto Loan Calculator
Calculate auto loan monthly payments online free — principal, rate, term and total interest for car financing. Runs entirely in your browser — nothing uploaded.
Auto loan payment with tax & trade-in
- Monthly payment$523.20
- Total amount financed$26,740
- Sales tax added$1,740
- Total trade-in & cash down$7,000
- Total interest over term$4,652
- Total vehicle cost$38,392
Calculated in your browser — nothing you type is sent anywhere.
An auto loan calculator that includes the two things dealers rarely put in front of you: the sales tax rolled into the loan, and the total cost of the vehicleonce interest is counted. Enter price, down payment, trade-in, tax rate and terms. Everything is computed in your browser and nothing is transmitted.
The default example, line by line
A $32,000 vehicle with $4,000 down, a $3,000 trade-in and 6% sales tax at 6.5% over 5 years:
| Output | Value | How it is worked out |
|---|---|---|
| Sales tax added | $1,740 | 6% of $32,000 − $3,000 trade-in |
| Total trade-in & cash down | $7,000 | $4,000 deposit + $3,000 trade-in |
| Total amount financed | $26,740 | $32,000 + $1,740 tax − $7,000 |
| Monthly payment | $523.20 | $26,740 at 6.5% over 60 months |
| Total interest over term | $4,652 | 60 payments less the amount financed |
| Total vehicle cost | $38,392 | All payments + everything you put down |
Compare the first and last rows: a car advertised at $32,000 costs $38,392 by the time tax and interest are paid — about $6,400 over the sticker. That gap is the number worth negotiating against, and it is the one no window sticker shows.
Trade-in beats a private sale more often than people think
Most US states charge sales tax on the price minus your trade-in, not the full price, and that changes the arithmetic of selling privately. On the defaults, the $3,000 trade-in removes $180 of tax as well as $3,000 of principal.
So a private buyer has to beat the dealer's offer by more than the difference in headline price to actually leave you better off — at a 6% rate the tax saving alone is 6% of whatever the trade-in is worth. On a $10,000 trade that is $600 before you count the hassle of selling. If your state taxes the full price regardless, set trade-in to zero here and add its value to the down payment instead, and the maths stays exact.
You are financing the tax, and paying interest on it
The amount financed is not price minus deposit. It is price plus tax, minus your deposit and trade-in. Rolling tax into the loan is standard practice and almost nobody objects to it, but it has a consequence: every dollar of sales tax accrues interest for the whole term. On the defaults, $1,740 of tax financed over five years at 6.5% costs about $300 in interest on top of the tax itself.
Paying the tax in cash at signing, if you can, is one of the cheapest improvements available to a car deal — and it never appears in the payment comparison a finance office puts in front of you.
Term and deposit, in dollars
| Change | Monthly payment | Total interest |
|---|---|---|
| Default — 5 years, $4,000 down | $523.20 | $4,652 |
| Term stretched to 7 years | $397.07 | $6,614 |
| Term shortened to 3 years | $819.55 | $2,764 |
| Deposit doubled to $8,000 | $444.93 | $3,956 |
The term rows are the trap. Going to seven years saves about $126 a month and costs $1,962 more in interest — and worse, it keeps you underwater for longer, owing more than the car is worth, because vehicles depreciate faster than a long loan amortises. That matters the moment you want to sell, or if the car is written off and the insurer pays market value rather than your balance.
How to use this in the finance office
- Get a rate from your own bank first and enter that, not the dealer's, as your baseline.
- Add fees and add-ons to the price if you plan to finance them, so the payment is honest.
- Compare offers on total interest, not monthly payment. Two deals with identical payments can differ by thousands.
- Test the shorter term before accepting the longer one. If the shorter payment is affordable, the saving is substantial.
- Check the total vehicle cost row against the sticker. That difference is your real negotiating target.
Out of scope, deliberately: gap insurance, extended warranties as separate items, variable rates, balloon payments, negative equity rolled in from an existing loan, and registration or title fees. Fold anything you are financing into the price; budget the rest separately.
Related calculators
If the dealer is offering a rebate or cheap financing, thecash back vs low interest calculator prices both paths. To see what overpaying does to an existing loan, use thecar payment calculator, andauto lease calculator breaks a lease into depreciation and finance charge if you are weighing leasing instead. For unsecured borrowing, thepersonal loan calculator models origination fees, and theloan payment calculator covers the general case. Sales tax on its own is the sales tax calculator.
Frequently Asked Questions
What does the default example show?
A 32,000 dollar vehicle with 4,000 dollars down, a 3,000 dollar trade-in and 6 percent sales tax, financed at 6.5 percent over 5 years. That gives a payment of 523.20 dollars a month on 26,740 dollars financed, with 4,652 dollars of interest and a total vehicle cost of 38,392 dollars.
Why is sales tax charged on the price minus my trade-in?
Most US states tax only the difference between the vehicle price and your trade-in, which is one of the quietest benefits of trading in rather than selling privately. On the defaults that saves 180 dollars of tax. If your state taxes the full price, set the trade-in to zero and add its value to the down payment instead.
Is the amount financed just price minus down payment?
No, and this is where most estimates go wrong. It is the price, plus sales tax, minus your down payment and trade-in. On the defaults that is 32,000 plus 1,740 of tax minus 7,000, giving 26,740 dollars — so you are financing the tax and paying interest on it too.
Should I take a longer term to lower the payment?
Compare the total interest row before you do. Stretching the default loan from 5 years to 7 drops the payment by about 126 dollars but adds roughly 1,962 dollars of interest, and it keeps you underwater for longer because cars lose value faster than a long loan pays down.
How much does the down payment actually save?
On the defaults, going from 4,000 dollars down to 8,000 cuts the payment from 523.20 to 444.93 dollars and the interest from 4,652 to 3,956 — about 696 dollars saved. It is the only field that reduces every other number on the page, and a larger deposit may also qualify you for a better rate.
What about dealer fees, warranties and add-ons?
They vary far too much to model as a field, so add them to the vehicle price if you intend to finance them and the arithmetic stays exact. Documentation fees, extended warranties, paint protection and gap insurance all get rolled into the loan in practice, and all accrue interest.
What happens at a zero percent promotional rate?
It is handled correctly rather than erroring: the payment becomes the amount financed divided by the number of months and the total interest is zero. Worth running against a cash rebate offer, since dealers usually make you choose between the two.
Is anything I enter sent anywhere?
No. Every figure is computed in your browser with JavaScript, so prices, deposits, trade-in values and rates never leave your device and nothing is stored or logged. Useful when you are checking a finance quote on your phone while sitting in the dealership.