Auto Loan Calculator
Car loan payment with trade-in value, payoff owed, cash down, sales tax and fees you enter: amount financed, total interest, total paid and negative equity.
Interactive calculator · Method AUTO-LOAN-1.0 · Last reviewed: 2026-11-04
Calculate your scenario
Sales tax = tax rate × (price − trade-in value, or the full price, as you choose).
Your inputs
Default worked example. Edit the inputs to calculate your scenario.
Default worked example
Financed $35,000.00 + $1,500.00 tax + $800.00 fees − $10,000.00 trade-in + $8,000.00 payoff − $3,000.00 down = $32,300.00; at 6.5% for 60 months the payment is $631.99.
How to use the calculator
Enter the price, trade-in value and what you still owe on it, cash down, your sales tax rate and how it applies, fees and whether you finance them, then the APR and term.
What the result means
A $35,000 car with a $10,000 trade-in ($8,000 still owed), $3,000 down, 6% tax on the net price and $800 financed fees finances $32,300; at 6.5% APR over 60 months that is about $632 a month.
Formula and units
Sales tax = tax rate × (price − trade-in value, or the full price, as you choose). Amount financed = price + sales tax + financed fees − trade-in value + payoff owed − cash down (floored at $0). Monthly payment M = A·r ÷ (1 − (1 + r)^−n) with r = APR ÷ 12 ÷ 100 and n months; at 0% APR, M = A ÷ n. Total interest = M × n − A. Total paid = cash down + up-front fees + M × n.
Worked examples
$35,000 car, $10,000 trade-in with $8,000 owed, 6.5% for 60 months: Vehicle price: 35000 USD; Trade-in value: 10000 USD; Loan payoff owed on the trade-in: 8000 USD; Cash down payment: 3000 USD; Sales tax rate (enter your rate): 6 %; Title, registration and doc fees (example): 800 USD; Loan APR: 6.5 %; Loan term: 60 months; Sales tax applies to: net; Fees are: financed.
Example result: Monthly payment: $631.99; Amount financed: $32,300.00; Total interest: $5,619.20; Total of payments and cash paid up front: $40,919.20; Sales tax: $1,500.00; Negative equity rolled into the loan: $0.00.
$28,000 car with $3,500 negative equity, 8.9% for 72 months: Vehicle price: 28000 USD; Trade-in value: 6000 USD; Loan payoff owed on the trade-in: 9500 USD; Cash down payment: 1000 USD; Sales tax rate (enter your rate): 7 %; Title, registration and doc fees (example): 600 USD; Loan APR: 8.9 %; Loan term: 72 months; Sales tax applies to: full; Fees are: paid.
Example result: Monthly payment: $583.50; Amount financed: $32,460.00; Total interest: $9,551.94; Total of payments and cash paid up front: $43,611.94; Sales tax: $1,960.00; Negative equity rolled into the loan: $3,500.00.
Limitations and common mistakes
Whether your trade-in reduces the taxable price depends on where you buy; choose it explicitly here. Tax rate, fees and APR are your entries. Rebates, dealer add-ons, service contracts, GAP coverage and per-period rounding by the lender are not modeled, and the payment is an estimate, not a loan offer.
Subtracting the trade-in value without adding back the payoff owed hides negative equity that ends up in the new loan.
Sources and assumptions
Method AUTO-LOAN-1.0; last formula review 2026-11-04. Sources and their supported claims. Calculation methodology.