# Auto Loan Calculator > Calculate Your Monthly Car Payment and Total Loan Cost Free auto loan calculator. Calculate monthly car payments with vehicle price, down payment, trade-in, sales tax, APR, and loan term. Compare 24-84 month terms with full amortization schedule. No signup, 100% private browser tool. URL: https://tools.scoreroute.com/tools/auto-loan-calculator/ Markdown: https://tools.scoreroute.com/tools/auto-loan-calculator/.md ## Calculate Your Car Payment ### Term Comparison ## How This Auto Loan Calculator Works This calculator uses the standard amortization formula to compute your monthly car payment. The formula is: M = P × [r(1+r)^n] / [(1+r)^n - 1], where M is the monthly payment, P is the loan principal (vehicle price + tax - down payment - trade-in), r is the monthly interest rate (APR / 12), and n is the number of months. ## Why AI Cannot Replace This Tool Large language models frequently hallucinate auto loan calculations. They misapply amortization formulas, confuse APR with monthly rates, mishandle sales tax, and produce inconsistent results for the same inputs across different conversations. This tool uses deterministic JavaScript math with no approximation, no hallucination, and no variability. Every calculation is bit-exact and reproducible. ## Frequently Asked Questions **What is a good APR for a car loan in 2026?** As of mid-2026, the average APR for a 60-month new car loan is approximately 6.97%. Super prime borrowers (FICO 781+) can qualify for rates as low as 4.66%, while deep subprime borrowers (FICO below 500) face rates up to 16.01%. Credit unions typically offer rates 0.4-0.6% below commercial banks. **How much car can I afford?** The standard guidance is to keep total monthly auto costs (loan payment + insurance + fuel + maintenance) under 15% of your monthly take-home pay. The 20/4/10 rule recommends: at least 20% down payment, maximum 4-year loan term, and total transportation costs under 10% of gross income. **Should I get a 72-month or 84-month car loan?** Longer terms lower your monthly payment but significantly increase total interest paid and extend the period you are underwater on the loan. For example, a $30,000 loan at 7% costs $594/month for 60 months ($5,640 interest) vs $476/month for 84 months ($9,969 interest). The 84-month term costs $4,377 more in interest. Choose the shortest term you can afford. **How does sales tax affect my car loan?** Sales tax is typically added to the vehicle price and financed as part of the loan. Rates vary by state: Oregon charges 0%, Texas 6.25%, California 7.25% (higher with local additions). Rolling tax into the loan means you pay interest on it for the entire term, increasing your total cost. This calculator includes sales tax in the loan amount for an accurate estimate. **What is the difference between APR and interest rate?** APR (Annual Percentage Rate) includes both the interest rate and any fees or costs associated with the loan, giving you the true cost of borrowing. The interest rate is just the cost of borrowing the principal. APR is always equal to or higher than the interest rate. When comparing loans, always compare APR, not just the interest rate. **Can I pay off my auto loan early?** Yes, and this calculator shows you exactly how much you save by making extra payments. Even an extra $50/month can save hundreds in interest and shorten your loan by months. However, check your loan agreement for prepayment penalties before making extra payments. Some lenders charge a fee for early payoff, typically 1-2% of the remaining balance. **Does this tool save my financial data?** No. All calculations happen entirely in your browser using JavaScript. Your financial data never leaves your device, is never stored on any server, and is never transmitted over the internet. This is 100% private. You can verify this by checking the Network tab in your browser's developer tools. **How accurate is this calculator compared to a dealer's quote?** This calculator uses the standard amortization formula that matches what banks and credit unions use. The results will match a dealer's quote within pennies if the same inputs are used. However, dealer quotes may include additional fees (documentation, title, registration, extended warranty) that this calculator does not include. Always get the out-the-door price before comparing. ## References - [ISO 4217 — Currency Codes](https://www.iso.org/iso-4217-currency-codes.html) - [Bank for International Settlements](https://www.bis.org/)