Auto loan calculator
Build your car financing estimate from the vehicle price, down payment, trade-in payoff, sales tax and fees. Compare interest costs and extra payments.
- Export
- United States
- US Dollar
Amount financed
Total interest
Total loan payments
Old debt carried into the purchase: . Your payoff exceeds your trade-in value. The difference increases the funding required.
No loan is needed for these inputs. Interest and loan payments are zero.
Total
- Purchase price including taxes and fees
- —
- Tax added
- —
- Fees added
- —
- Net trade-in equity
- —
- Cash paid at signing
- —
- Purchase price plus interest
- —
- Net cash paid over the whole transaction
- —
- Trade-in surplus returned
- Down payment not needed
Where the purchase cost goes
- Vehicle—
- Tax—
- Fees—
- Interest—
Loan balance and cumulative payments
- Remaining balance
- Principal repaid
- Cumulative interest
- Cumulative payments
On a narrow screen, scroll the chart horizontally to read the axes and the full time range.
Principal and interest by year
- Principal repaid
- Interest paid
- Year-end balance
On a narrow screen, scroll the chart horizontally to read the axes and the full time range.
Amortization schedule
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How does this tool work?
A car payment starts with more than the sticker price. This calculator builds the amount you need to finance from the agreed vehicle price, cash down payment, trade-in allowance, existing loan payoff, sales tax and fees. It shows a fixed-rate monthly estimate, the interest cost, charts and a downloadable schedule. Amounts are in US dollars and the inputs follow US car-buying practice: sales tax added to the price, dealer fees and trade-in payoff. For a purchase elsewhere, the general loan calculator is a better fit.
Choose a vehicle price before taxes and fees, or an out-the-door quote that already includes them. In the first mode, enter a tax rate or an exact tax amount and add title, registration and dealer fees. In the all-in mode, those extra fields are ignored. Enter the agreed price after discounts; use an exact tax amount when the taxable price differs from the discounted price.
Trade-in equity is the allowance minus the payoff on the old loan. Positive equity reduces the new financing; negative equity increases it. Ask for the actual payoff because it can differ from a statement balance. If a trade-in tax deduction applies, it uses the allowance itself, not the equity left after paying the old loan. That option is off by default and does not assume that every state or transaction qualifies.
The annual interest rate is divided by twelve. Each payment covers interest on the outstanding balance, then reduces principal. Amounts are rounded to cents and the final contractual payment settles the remaining balance. Extra monthly principal reduces later interest and may end the loan earlier. Paying taxes and fees upfront reduces financing but increases the cash needed at signing.
How to use this tool
Enter the purchase terms
Choose the price basis, then enter price, down payment and any trade-in with its existing payoff.
Check taxes and financing
Enter the applicable tax and fees, decide whether to finance them, then set the interest rate and term in months.
Compare the full cost
Compare purchase cost with loan cost. Try an extra payment, inspect the charts and download the monthly or yearly schedule.
From purchase price to monthly payment
Separate the car transaction from repayment of the resulting fixed-rate loan.
Net trade-in equity
E = S − R
Trade-in allowance S minus existing payoff R; E can be negative.
Amount financed
P = max(0, V + T + F − E − A − C)
Vehicle price V, added tax T and fees F, less net equity E, applied down payment A and tax/fees C paid upfront.
Fixed monthly payment
M = P × i / (1 − (1 + i)^(−n)); i = r / 1200. If r = 0: M = P / n.
Nominal annual rate r in percent; n monthly payments. The last payment absorbs cent rounding.
- P, M
- amount financed and base monthly payment, in US dollars
- r, n
- annual interest rate in percent and agreed term in months
No lender offer, credit approval, state tax lookup, balloon payment or lease calculation is included.
Use cases
Check a dealer quote
Reconcile the amount financed with the price, fees, deposit and net trade-in value.
Compare loan terms
Keep the price and rate unchanged to see how a longer term changes the monthly payment and total interest.
Replace a financed car
Include the old payoff instead of treating the full trade-in allowance as available equity.
Examples
Financed taxes and fees
The all-in purchase price is $32,300. The down payment reduces financing, not the purchase price. The final payment can differ by a few cents.
Input
$30,000 vehicle; $5,000 down; 6% sales tax; $500 fees; 6% interest; 60 months; no trade-in.Result
$27,300 financed; $527.79 base payment; $4,367.11 interest; $36,667.11 purchase price plus interest.A trade-in with negative equity
The old loan adds $2,000 to the funding required. It does not disappear when the dealer takes the vehicle.
Input
Same purchase; $8,000 trade-in allowance; $10,000 payoff; no trade-in tax deduction.Result
$2,000 negative equity; $29,300 financed; $566.45 base payment over 60 months.Pay an extra $100 per month
The base payment stays $527.79. Extra principal is paid after the regular payment; the final payment is limited to the amount still due.
Input
First example with $100 in extra principal each month.Result
50 payments instead of 60; $3,560.29 interest; $806.82 interest saved.Tips and best practices
- Use an exact tax figure from the quote if local rules tax fees, cap a trade-in credit or use a different taxable price.
- Net cash outlay includes the old payoff and trade-in credit. Purchase price plus interest is a different total; neither includes insurance, fuel, maintenance or future resale value.
- Sales tax rates differ by state and sometimes by county or city. Take the combined rate, or the exact tax amount, from the dealer quote.
Sources and references
- CFPB — How does paying down a mortgage work? (opens in a new tab)Page in English
- What is the difference between a loan interest rate and the APR? (opens in a new tab), Consumer Financial Protection BureauPage in English
- Should I trade in my car if it’s not paid off? (opens in a new tab), Consumer Financial Protection BureauPage in English
- What’s the difference between a simple interest rate and precomputed interest on an auto loan? (opens in a new tab), Consumer Financial Protection BureauPage in English
- Motor Vehicle Tax Guide — Trade-Ins (opens in a new tab), Texas Comptroller of Public AccountsPage in English
Frequently asked questions
Can I use APR instead of the interest rate?
The schedule uses the contractual interest rate. APR includes certain financing costs and may be higher. Substituting APR while also adding those costs can overstate the estimate. This tool does not calculate a legally disclosed APR.
Does it calculate tax for every US state?
No. Enter the applicable rate or exact tax and decide whether a trade-in deduction applies. Rate mode does not automatically tax fees or enforce state caps. Check the quote and local rules.
How do I enter an out-the-door price?
Choose the all-in price mode and enter that total once. Separate taxes and fees are ignored. The down payment, trade-in and old payoff still affect financing.
What if no borrowing is needed?
The loan, interest and schedule become zero. Any unused proposed down payment and trade-in surplus are shown separately. Negative net cash outlay means you receive money back overall.
Why might my lender’s schedule differ?
Many auto loans calculate simple interest daily instead of using equal monthly periods. The first payment interval, actual dates, extra products and rounding rules can also change a quote. Precomputed-interest and balloon loans are outside this model.
Are extra-payment savings guaranteed?
They assume extra payments reduce principal without penalties or fees. Confirm how your lender allocates payments and handles early repayment.
Are my purchase details uploaded?
Calculation, charts and CSV export run in your browser. A shared calculation link stores the values in its URL fragment; share it only if you want the recipient to see those figures.
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