Car Loan Calculator
Price, down payment, trade-in, sales tax and APR: see the amount you're actually financing and your real monthly payment.
How this calculator works
A car loan isn't just the sticker price. This calculator builds your real amount financed step by step:
- Sales tax is calculated on the price minus your trade-in (most states give a trade-in tax credit, yours may work differently, see assumptions below).
- That tax is added to the price.
- Your down payment and trade-in value are subtracted.
- What's left is financed using the standard fixed-rate loan formula.
Worked example
$30,000 car, $3,000 down, $5,000 trade-in, 6% sales tax, 5.5% APR, 60-month term: sales tax is $1,500 (6% of $25,000), so the amount financed is $23,500, and the monthly payment is about $448.88.
Frequently asked questions
Does every state tax trade-ins the same way?
No. Most states only tax the difference between the new car's price and your trade-in, but a handful tax the full price. Check your state's DMV or revenue department for the exact rule.
Should I put my trade-in toward the down payment or let it reduce the tax?
In states with a trade-in tax credit, the trade-in value reduces your tax bill automatically whether you think of it as "down payment" or not. This calculator applies that credit either way.
What about title, registration and dealer fees?
Those vary a lot by state and dealer and aren't included here. Ask for an out-the-door price that itemizes every fee before you sign.
Is a longer term always worse?
A longer term lowers your monthly payment but increases total interest paid and keeps you "underwater" (owing more than the car is worth) for longer. Compare total interest, not just the monthly number.
Assumptions & sources
- Sales tax is calculated on (price − trade-in), the common trade-in tax credit rule used by most states. Your state may differ.
- No title, registration, dealer, or documentation fees included.
- Fixed-rate loan, standard amortization formula.
Educational estimates, not financial advice.