An auto loan’s payment depends on more than the sticker price. This works out the amount actually financed — after sales tax, down payment and trade-in — and the resulting monthly payment.
How it works
Amount financed
financed = (price + sales tax) − down payment − trade-in value
The financed amount then runs through the same standard amortization formula every loan calculator on this site uses.
A car is a depreciating asset — this calculator only computes the loan
Unlike a home, which over the long run tends to hold or gain value, a vehicle’s value falls the moment it’s driven off the lot and keeps falling. Financing a car for longer than you’d keep it, or with too small a down payment, risks owing more than the car is worth — being “upside down” on the loan — for a real stretch of the term. This calculator reports the payment and total interest; whether the term and down payment are sound is a separate judgment it doesn’t make.
How to use this calculator
- Enter the vehicle price and your local sales tax rate.
- Enter any down payment and trade-in value.
- Enter the APR and loan term.
Frequently asked questions
Does trade-in value reduce sales tax too?
In many places, yes — some jurisdictions only tax the price minus the trade-in, not the full price. This calculator applies tax to the full price before subtracting trade-in; check your local rules if trade-in tax credit applies where you are, and adjust the tax figure accordingly.
Why does a shorter loan term usually mean a lower total cost?
Because a shorter term means less time for interest to accrue on the outstanding balance — a higher monthly payment, but generally less total interest paid over the life of the loan.
What does it mean to be “upside down” on a car loan?
Owing more on the loan than the car is currently worth — a real risk with long loan terms and low down payments, since cars depreciate quickly, especially in the first few years.
Should I finance the maximum term to get the lowest payment?
A lower monthly payment from a longer term generally means more total interest paid and a longer period of being upside down — worth weighing against the lower monthly cost rather than choosing on payment size alone.
Does this calculator include registration or other fees?
No — only price, sales tax, down payment, trade-in and financing. Registration, documentation and other fees vary by state and dealer and aren’t included here.
