Auto Loan Calculator With Taxes and Fees

How to use this calculator

Enter the written vehicle price and estimated tax rate. Add title, registration, document, delivery, and other fees as one dollar amount. Keep optional products separate. Enter cash down, the trade-in credit, any payoff still owed on that trade, the APR, and the number of monthly payments.

When this calculator is useful

• Comparing written out-the-door offers
• Testing 48-, 60-, and 72-month loan terms
• Seeing how add-ons or negative equity raise the payment
• Comparing dealer financing with a bank or credit-union preapproval

Important limitations

This is a fixed-rate installment-loan estimate. Tax rules differ by location, including whether a trade-in reduces the taxable price. The tool does not include insurance, fuel, maintenance, late fees, prepayment penalties, variable rates, or balloon payments.

For best results, run at least three cases: a conservative case, a middle case, and a stretch case. If a small change in inputs creates a big change in the answer, that is a sign the decision may be sensitive to rates, fees, timing, or market performance.

Start with the out-the-door price, not the advertised payment

An auto loan payment begins with the amount financed, not the number printed on a window sticker. The vehicle price can be joined by sales tax, title and registration charges, document or delivery fees, optional products, and debt from a trade-in that is worth less than its loan payoff.

The Federal Trade Commission recommends asking for the out-the-door price in writing before visiting a dealer. That figure should include charges and fees. Keep financing terms separate while negotiating so a discussion about the monthly payment does not blur a change in vehicle price, loan term, or add-ons.

This calculator keeps those pieces visible. If a quote already gives one final out-the-door price, enter that amount as the vehicle price, set tax and fees to zero, then subtract cash down and net trade equity as appropriate. Do not add the same charge twice.

How the amount financed is calculated

The calculator uses this planning formula:

Amount financed = vehicle price + estimated tax + fees + add-ons + trade payoff − cash down − trade value.

Estimated tax equals the vehicle price multiplied by the entered tax rate. Actual state and local rules may tax a different base. Some locations reduce the taxable amount for a trade-in; others handle credits, rebates, and fees differently. Use the buyer’s order or a written quote when available.

If the result falls below zero, the calculator uses zero as the financed amount. Cash due at signing and refundable credits should still be confirmed from the contract.

Worked example: a $32,000 vehicle

Suppose a written deal has a $32,000 vehicle price, 7% estimated sales tax, $850 of title, registration, and dealer fees, no add-ons, a $4,000 cash down payment, and a trade worth $3,000 with $1,000 still owed. At 7.5% APR for 60 months:

• Estimated sales tax is $2,240.
• The estimated out-the-door price before down payment or trade is $35,090.
• The trade contributes $2,000 of net equity because its $3,000 value exceeds the $1,000 payoff.
• The modeled amount financed is $29,090.
• The estimated payment is $582.90 a month.
• Sixty modeled payments total about $34,974.24, including roughly $5,884.24 of interest.

These are hypothetical inputs, not a current average rate or a dealer quote. The payment uses standard monthly amortization and assumes every payment arrives on time.

Compare terms without looking only at the payment

Using the same $29,090 balance and 7.5% APR, a 48-month term produces an estimated $703.36 payment and $4,671.48 of interest. A 72-month term lowers the payment to about $502.97 but raises estimated interest to $7,123.79.

The 72-month option is about $200 less per month than the 48-month option in this example, yet it adds roughly $2,452 of modeled interest. A lower payment is useful only when the complete term and cost also fit the plan.

The Consumer Financial Protection Bureau warns that longer terms generally increase total interest and can leave the borrower exposed to negative equity for longer.

Trade-in value is not the same as trade equity

A dealer may credit $15,000 for a trade while the existing lender is still owed $18,000. The trade has $3,000 of negative equity, not a $15,000 down payment. If that $3,000 is rolled into the next contract, the new loan starts with old debt attached.

Enter $15,000 as trade-in value and $18,000 as trade-in loan payoff. The calculator adds the net $3,000 shortfall to the amount financed. If the trade is worth $18,000 and the payoff is $15,000, the same fields subtract $3,000 of net equity instead.

Get the payoff directly from the current lender and check its valid-through date. A statement balance can differ from a payoff quote because interest and fees may continue to accrue.

Keep optional add-ons on their own line

Service contracts, extended warranties, GAP products, credit insurance, wheel or tire coverage, and appearance products can be presented late in the sale. The CFPB says optional add-ons increase both the amount borrowed and the payment when they are financed.

Put their total in the add-ons field, then run the calculator once with them and once without them. The difference is larger than the sticker price because financing an add-on also creates interest. Ask for each product’s price, coverage, cancellation terms, and whether it is required. Do not assume a product is mandatory because it appears in a payment quote.

Use the Truth in Lending disclosure as the final check

Before signing, compare the contract’s APR, finance charge, amount financed, total of payments, payment count, and payment amount. The calculator is a way to question a quote; the signed disclosure controls the actual obligation.

A useful comparison sheet has one row per lender or dealer and records the same fields for each offer. Get a bank or credit-union preapproval when possible, then compare it with dealer-arranged financing using the same vehicle price, down payment, and term.

Also ask about a prepayment penalty. Paying principal early can reduce interest on many simple-interest auto loans, but the contract determines how payments are applied and whether a fee exists.

Budget for the car after the loan payment

The calculated payment is not the monthly cost of owning the vehicle. Price insurance before buying, especially when a lender requires collision and comprehensive coverage. Add fuel or charging, maintenance, tires, registration renewals, parking, and a repair allowance.

If a loan payment only fits after excluding those costs, the vehicle does not fit the same budget. The CFPB’s auto-loan affordability guidance recommends evaluating the purchase and ongoing ownership costs together.

For an existing loan, use the car-loan extra-payment guide to model faster payoff. The monthly payment and total-cost guide explains amortization and quote comparisons in more detail. Use the emergency fund calculator before committing all available cash to a down payment.

Sources and method notes

• Consumer Financial Protection Bureau: Take control of your auto loan — budgeting, loan shopping, negotiation, and total-cost comparisons.
• Consumer Financial Protection Bureau: how much can I afford to borrow? — up-front costs, trade-ins, down payments, loan term, and ongoing ownership costs.
• Consumer Financial Protection Bureau: negotiable auto-loan terms — APR, term, add-ons, trade value, negative equity, and fees.
• Federal Trade Commission: Car Dealer Ads and Promotions — written out-the-door prices, advertised payments, add-ons, and financing disclosures.

Method reviewed September 17, 2026. The calculator runs in the browser and does not store vehicle or loan inputs.

Educational only. This calculator provides general information, not personalized financial, legal, tax, lending, insurance, or vehicle-purchase advice.

Frequently asked questions

What is included in the amount financed?

The model adds vehicle price, estimated sales tax, entered fees, optional add-ons, and the old loan payoff. It then subtracts cash down and trade-in value. Your retail installment contract may use different tax rules or classify charges differently.

Why should I enter the trade-in value and payoff separately?

A trade-in worth more than its payoff contributes positive equity. A payoff larger than the trade value creates negative equity that can be rolled into the new loan. Combining the two numbers can hide how much old debt is being financed again.

Does a longer term make the car cheaper?

No. A longer term usually lowers the required monthly payment but keeps the balance outstanding longer. At the same APR and amount financed, that normally increases total interest and can extend the period when the loan balance is higher than the car value.

Should I enter the interest rate or APR?

Use the disclosed APR when comparing credit offers. APR is the yearly cost of credit expressed as a rate and can differ from the contract interest rate when certain finance charges apply. Compare the calculator result with the lender’s Truth in Lending disclosure.

Does the payment include insurance and maintenance?

No. Insurance, fuel, repairs, tires, registration renewals, and routine maintenance affect affordability but are not loan payments. Add them to a separate monthly vehicle budget.