Enter the price, down payment, trade-in, sales tax and rate to get your monthly car payment and total interest.
How this calculator arrives at its answer
This auto loan calculator builds the real loan amount from the vehicle price, your down payment, any trade-in and sales tax, then works out the monthly payment.
Seeing tax and interest separately helps you understand the true cost of financing a car.
Step by step
- Enter the vehicle price and your down payment.
- Add any trade-in value and your sales tax rate.
- Enter the rate and term to see the monthly payment.
The formula
loan = price − down − trade-in + sales tax
payment = loan × r ÷ (1 − (1+r)⁻ⁿ)
Worked example
Worked through, a vehicle price of 35,000 produces a monthly payment of $650.23. Underneath, Loan amount comes out at $32,450 and Sales tax at $2,450. Change any field and every figure updates as you type.
Questions people ask about this
How is a car payment calculated?
The financed amount (price minus down payment and trade-in, plus tax) is amortized over the term at the monthly interest rate.
Is sales tax financed?
Often yes — many buyers roll tax into the loan. Many states tax the price after the trade-in credit, which this tool assumes.
How can I lower the payment?
A bigger down payment, a lower rate, or a shorter term (which raises the payment but cuts total interest). This is an estimate, not advice.