Is sales tax always calculated on price minus trade-in?

Not everywhere — most US states tax the price after subtracting trade-in value, but a handful tax the full purchase price regardless. Check your state's rule if the estimate needs to be precise.

Why is a 72-month loan's total interest so much higher than a 60-month loan's?

The same reason any amortizing loan costs more over a longer term: interest accrues on the outstanding balance for more months, even though each individual payment is smaller.

Does a 0% promotional rate mean I pay no interest at all?

If the rate is genuinely 0%, the calculator switches to splitting the amount financed evenly across the term with no interest component — matching what a true 0% APR offer means.

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Finance

Auto Loan Calculator

Monthly car payment including trade-in and sales tax.

🔒 Runs entirely in your browser — nothing here is ever uploaded

About the Auto Loan Calculator

Calculates your monthly car payment from the vehicle price, down payment, trade-in value, sales tax, interest rate, and loan term, using the same fixed-rate amortizing-loan formula as the Loan EMI and Mortgage calculators.

How to use it

Enter the Vehicle price, Down payment, and Trade-in value (if any).
Enter your local Sales tax rate.
Enter the Interest rate and choose a Loan term.
Read your monthly payment, amount financed, and total interest in the result panel.

Formula

Amount financed = vehicle price + sales tax − down payment − trade-in value
Monthly payment = P × r × (1+r)ⁿ ÷ [(1+r)ⁿ − 1]
P = amount financed, r = monthly interest rate, n = number of monthly payments

The same present-value-of-an-annuity formula as any other fixed-rate amortizing loan — see the Loan EMI calculator's sourcing for the underlying math. Sales tax here is estimated on the price minus trade-in, the common convention in many (not all) US states — some states tax the full price regardless of trade-in, so treat the tax estimate as approximate for your state.

Worked example

A $32,000 vehicle with a $4,000 down payment, no trade-in, 7% sales tax, financed at 7.5% over 60 months, comes to about $606/month — $30,240 financed against roughly $6,117 in total interest.

Recommendations

• A trade-in reduces both the amount financed and, in most states, the taxable amount — it's worth more toward a purchase than its cash value alone suggests.
• Shorter terms mean higher payments but meaningfully less total interest — compare 48 vs. 72 months on the same numbers.
• This estimates sales tax only — title, registration, and dealer fees vary by state and aren't included.

Frequently asked questions

No — this estimates the vehicle price, sales tax, and financing only. Title, registration, documentation, and dealer fees vary by state and dealer, so add those separately.