Auto Finance Calculator
Model the monthly payment on a financed purchase or a lease. Figures are estimates — the rate you actually qualify for depends on your credit profile and the program attached to the specific vehicle.
A higher contract APR increases the borrower's total interest cost. Compare the final rate with written preapprovals and lender disclosures available to you, and ask the dealer or lender to explain any difference before you sign.
Consult an Advisor →Understanding the Inputs
Five numbers drive the payment on nearly every retail car deal. This tool lets you adjust each one and watch the effect.
Vehicle Price is the agreed selling price before tax, title, and government charges — not the sticker. For the tightest estimate, take your out-the-door figure and strip out taxes and government fees.
Down Payment is the cash you bring to signing. Trade-in equity has its own lines, so leave it out here.
Net Trade Equity is the trade-in value minus any loan payoff. Positive equity reduces the new loan; negative equity increases it. Enter both figures so the calculator does not treat the trade's gross value as cash you can apply to the purchase.
Interest Rate (APR) is the annualized borrowing rate shown in the financing documents. Compare it with written preapprovals and disclosures on the same principal and term; even a modest difference can materially change total interest.
Loan Term is how many months the financing runs. Stretching it shrinks the monthly payment while raising the total interest you pay.
The results show your estimated monthly payment, the interest paid across the full term, and what the vehicle ultimately costs once that interest is folded in.
A Worked Example — The Real Price of a 1.5% Rate Markup
Take a $42,000 vehicle with $5,000 down, $3,000 of net trade equity, a 6.9% APR, and a 60-month term. That leaves $34,000 financed, an estimated monthly payment near $672, and roughly $6,300 in interest over the life of the loan.
Now compare that with a 5.4% APR on the same principal and term. The estimated payment is about $648 a month with roughly $4,900 in total interest.
The 1.5-point APR difference costs the borrower about $24 a month and roughly $1,400 over the full term. That is a borrower-cost comparison; it does not claim how much a lender or dealer earns, because compensation arrangements vary.
Before you sign, compare the rate in the final documents with the written approvals and disclosures available to you, and ask for an explanation of any difference.
Common Questions from Buyers
Is the interest rate the dealer quotes the same rate my lender approved?
Not necessarily. Compare rates only when the lender, principal, term, and other conditions match. Review written preapprovals and lender disclosures, then ask the dealer or lender to explain any difference before signing. The calculator can model the borrower-cost effect of two APRs without assuming who earns the difference.
How is a money factor different from an APR?
APR is the rate on a financed purchase; leases use a money factor instead. Multiply the money factor by 2,400 to get its rough APR equivalent — 0.00288, for instance, works out to roughly 6.9%. Lease quotes usually show the money factor rather than the APR, partly because the same cost of borrowing looks much smaller written that way.
Will stretching out the loan term save me money?
It lowers the payment, not the cost. Financing the same balance over 72 months instead of 60 can add several thousand dollars of interest by the time the loan is paid off. Most shoppers fixate on the monthly figure, but the number that actually decides whether the longer term is worth it is the total you pay over the full term.
Are sales tax and fees included in these results?
They are not. Sales tax, title and registration charges, and dealer documentation fees differ by state and by dealer, so this tool models only the financing side of the transaction. For a complete out-the-door figure built around your taxes, fees, and deal structure, request a consultation.
Disclaimer: The figures produced here are illustrative and educational only — they are not a financing offer, commitment, or guarantee. Your actual payment will depend on your credit profile, available lender programs, applicable taxes and fees, and the specifics of your transaction. Meridian Auto Advisory is not a lender, a dealership, or a financial advisor. Confirm your rate and terms directly with your lender before you sign anything.