Auto Finance Calculator
Estimate your monthly payment for a financed purchase or a lease. Results are illustrative — your actual rate depends on your credit profile and the specific vehicle program.
Dealers are permitted to mark up your approved financing rate — a practice called dealer reserve. A 1% markup on a $40,000 loan over 60 months adds approximately $1,000 in additional interest. Our advisors verify your buy rate against what the dealer is quoting before you sign.
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This calculator estimates your monthly payment based on five variables that drive nearly every retail auto transaction.
Vehicle Price is the negotiated price of the vehicle before tax, title, and government fees. This is not MSRP. Use the out-the-door price minus taxes and government fees if you want the most accurate estimate.
Down Payment is cash brought to the deal at signing. It does not include trade-in value, which is captured separately.
Trade-In Value is the dealer's offer for your current vehicle. The dealer's first offer is rarely their best offer. A vehicle's wholesale value at auction sets the floor on what the dealer can reasonably pay.
Interest Rate (APR) is your approved rate from the lender. This is the most-marked-up variable in the F&I office. The dealer is permitted to add margin to your approved rate — typically up to two percent — without disclosing the markup. The added margin becomes dealer reserve income.
Loan Term is the length of the financing in months. Longer terms reduce the monthly payment but increase total interest paid.
The output shows your estimated monthly payment, the total interest paid over the term, and the total cost of the vehicle once interest is included.
A Worked Example — What a 1.5% Rate Markup Actually Costs
Consider a $42,000 vehicle financed with $5,000 down, $3,000 in trade-in credit, a 6.9% APR, and a 60-month term. The loan amount is $34,000. The estimated monthly payment is approximately $672. Total interest paid over the life of the loan is approximately $6,332.
Now consider the same deal with the dealer having marked up the buyer's approved 5.4% APR to 6.9% — a 1.5% rate reserve. At the buyer's actual approved rate, the same loan produces a monthly payment of approximately $648 and total interest of approximately $4,892.
The 1.5% markup costs the buyer $24 per month and $1,440 over the life of the loan. That money does not go to the lender. It becomes dealer reserve income, paid to the dealership by the lender out of the marked-up rate.
This is the single most common F&I markup. It is legal. It is also rarely disclosed at the table. Our advisory verifies your buy rate against the rate the dealer is quoting before you sign.
Questions Buyers Commonly Ask
Is the rate the dealer quotes my actual approved rate?
Not always. Dealers are permitted to mark up your approved rate by up to two percent — sometimes more — without disclosing the markup. The added margin is called dealer reserve. It is one of the most common F&I markups and the easiest one to verify with the right documentation.
What is the difference between APR and money factor?
APR applies to financed purchases. Money factor applies to leases. To convert a money factor to its APR equivalent, multiply by 2,400. A money factor of 0.00288 is approximately equivalent to a 6.9% APR. Lease quotes are typically presented in money factor rather than APR because the equivalent rate sounds higher in conventional terms.
Should I take a longer loan term to lower my monthly payment?
A longer term reduces the monthly payment but increases total interest paid. A 72-month loan instead of a 60-month loan on the same principal can add several thousand dollars in interest. The monthly payment difference is what most buyers focus on; the total cost difference is what determines whether the trade is worth making.
Does this calculator include sales tax and fees?
No. Sales tax, title fees, registration, and dealer documentation fees vary by state and dealer. This calculator covers the financing portion of the deal only. For a complete out-the-door estimate that accounts for taxes, fees, and your specific deal structure, request a consultation.
Disclaimer: These calculations are for illustrative and educational purposes only. Results do not constitute a financing commitment or guarantee. Actual payments depend on your credit profile, lender programs, applicable taxes and fees, and the specific vehicle transaction. Negotiated is not a lender, dealer, or financial advisor. Always verify your rate and terms with your lender before signing.