Auto Loan Calculator
Build the amount financed from the vehicle price, tax, fees, down payment and trade-in balance. Then estimate monthly payments and total loan interest.
Auto Loan Calculator
Your inputs are calculated in your browser. No account is required.
Guide updated 6 October 2026
How to calculate a car payment from the full deal
Start with the negotiated vehicle price. Enter the cash down payment, the trade-in allowance and the amount still owed on the vehicle being traded. Add the actual tax amount and the fees that will be financed, followed by the annual contract interest rate and term in months.
This version takes a tax amount rather than choosing a country or state tax rate automatically. Use the buyer’s order or an applicable official tax calculation. The model assumes entered taxes and fees are financed; if you pay them separately, enter zero in those fields and track that cash cost yourself.
Amount financed, trade-in equity and the formula
Amount financed = vehicle price + financed tax + financed fees + trade-in debt − down payment − trade-in allowance. A trade worth 8,000 with 10,000 outstanding adds 2,000 of negative equity to the new loan in this model.
If the deductions exceed the purchase and debt costs, there is no positive amount to finance. The tool flags a negative result instead of creating a negative loan. Any surplus trade equity or refund must be resolved in the actual transaction.
Auto loan example with a down payment
For a vehicle priced at 30,000, a 5,000 cash down payment, 2,000 tax, 500 fees and no trade, the amount financed is 27,500. At 6% over 60 months, the estimated payment is about 531.65 per month.
The interest is calculated on the amount financed, including the tax and fees you put into the loan. Those fictional inputs are not regional tax rates or current lender rates. Repeat the calculation with actual written quotes.
Compare the interest rate, term and total repayments
The result shows the financed principal, monthly payment, interest and sum of loan payments. That sum does not include your down payment, the value of the traded vehicle or separately paid costs. Keep these distinct when comparing the full purchase.
A longer term may lower the monthly payment but increase interest and the time you owe money on a depreciating vehicle. The calculator does not predict resale value, insurance, fuel or repairs.
Contract interest and APR are different measures
Use the annual nominal interest rate that determines the contract’s payment. A disclosed APR may also reflect mandatory finance charges. The CFPB explains this distinction and the cost information US borrowers should receive before signing.
This tool does not calculate a legally disclosed APR or select a lender. A lease, balloon payment or Islamic financing contract can have a different structure and should not be represented as an ordinary amortizing loan without checking its terms.
Why a dealer quote may differ from the estimate
Check whether add-ons, warranties, registration and dealer charges were financed. Confirm the payoff amount on the trade-in, not just its original loan balance. Tax treatment of rebates and trade-ins varies by jurisdiction.
Daily simple-interest accrual and the first payment date can also change figures. Ask for a full written breakdown if the quote does not match the inputs. The repayment CSV helps you inspect the estimated principal reduction month by month.
Auto loan calculator FAQs
Does it automatically deduct trade-in value from taxable price? No. Enter the correct tax amount yourself. Can I use it outside the USA? Yes, provided the deal follows the stated loan model and the tax and fee amounts are accurate.
Can I finance an old vehicle’s outstanding debt? The estimate can include that debt, but lender approval and contract restrictions are separate. Does the result include ongoing ownership costs? No.