Auto Loan Calculator

About the Auto Loan Calculator

Buying a vehicle is one of the largest purchases most people make after a home. The auto loan calculator helps you understand exactly what your car will cost — not just the sticker price, but the true total cost including interest, sales tax, and fees.

Most car buyers focus on the monthly payment, but the real question is how much you pay over the life of the loan. A longer term lowers the monthly payment but dramatically increases total interest. A larger down payment or trade-in reduces the financed amount, saving thousands in interest.

This calculator accounts for all the factors: vehicle price, down payment, trade-in value, sales tax, dealer fees, interest rate, and loan term. You get the monthly payment, total interest, and complete cost of ownership — the information you need to negotiate confidently at the dealership. Knowing your numbers before walking in prevents common tactics like stretching the loan term to lower the payment while dramatically increasing total interest.

When This Page Helps

Dealerships focus on monthly payments to distract from total cost. This calculator shows both — so you can see how extending a loan from 48 to 72 months drops the payment but adds thousands in interest. Armed with this data, you negotiate from a position of knowledge. That clarity can easily save you a thousand dollars or more on a single purchase.

How to Use the Inputs

1. Enter the vehicle purchase price (MSRP or negotiated price).
2. Add your down payment amount and trade-in value if applicable.
3. Enter the sales tax rate for your state and any dealer fees.
4. Set the loan interest rate and term in months.
5. Review the monthly payment, total interest, and total cost of ownership.
6. Compare different terms (36, 48, 60, 72 months) to find the best balance of payment and cost.

Example Calculation

Tips & Best Practices

• Get pre-approved by your bank or credit union before visiting the dealer — it gives you negotiating leverage and a rate benchmark.
• Keep your loan term at 48–60 months maximum — 72- and 84-month loans incur excessive interest and risk being underwater.
• Negotiate the vehicle price first, then discuss financing — dealers sometimes lower the price if you use their financing.
• A larger down payment reduces interest cost and protects against negative equity (owing more than the car is worth).
• Consider total cost, not just monthly payment — a $50 lower payment over 72 months costs thousands more than 48 months.
• Factor in insurance, maintenance, and fuel when budgeting for a vehicle — the loan payment is only part of the cost.

Understanding Auto Loan Costs

The sticker price is just the beginning. Sales tax (typically 4–10% of the price), dealer documentation fees ($200–$800), registration fees, and optional add-ons all increase the amount you finance. Each additional dollar financed costs more over time due to interest.

The Term Length Trap

Dealers love to offer 72- and 84-month loans because the lower payments make expensive vehicles seem affordable. But a $35,000 car financed at 6.5% costs about $4,100 in interest over 48 months versus $7,700 over 72 months — nearly double. Worse, long terms increase the risk of negative equity.

Negotiation Strategy

Know your numbers before entering the dealership. Get pre-approved for financing, research the fair purchase price, and know your trade-in value. Negotiate the purchase price first, then compare the dealer's financing offer to your pre-approval. Choose whichever saves more in total cost.

Frequently Asked Questions

• What is a good auto loan rate?

  Rates vary by credit score, term, and whether the vehicle is new or used. As of recent years, excellent credit may get 4–6% for new cars and 5–7% for used. Good credit sees 6–9%. Fair credit may face 9–14%. Subprime borrowers can see 14–25%. Shorter terms typically get lower rates.

• How much should I put down on a car?

  Aim for at least 20% on a new car and 10% on a used car. This reduces your financed amount, lowers your payment, and helps you avoid being upside-down (owing more than the car is worth). A trade-in can count toward your down payment.

• Does trade-in value reduce the taxable amount?

  In most states, yes — your trade-in value is subtracted from the purchase price before sales tax is calculated. This can save hundreds or thousands in tax. However, rules vary by state, so check your local regulations.

• What loan term should I choose?

  The shortest term you can comfortably afford. A 48-month loan costs significantly less in total interest than a 72-month loan. The general rule: if you cannot afford the payment on a 60-month or shorter loan, the car may be too expensive for your budget.

• Should I lease or buy?

  Buying is generally cheaper long-term — you own the vehicle after the loan is paid off. Leasing offers lower monthly payments but you return the car with nothing to show for the payments. Use our Auto Lease vs Buy Calculator for a detailed comparison.

• Can I refinance an auto loan?

  Yes. If your credit improves or rates drop, refinancing can lower your rate and payment. You will need the current payoff amount, and the new lender will assess the vehicle value. Refinancing makes the most sense in the first half of the loan when interest charges are highest.