Auto Loan Calculator

Calculate the true monthly cost of a car including trade-in and taxes.

$
$
$
mo
%
%
Estimated Monthly Payment
$415.45
for 60 months
Total Loan Amount
$21,750.00
Total Interest Paid
$3,177.02
Estimated Sales Tax
$1,750.00
True Cost of Car
$29,927.02

How to Use

1

Enter the vehicle price

Input the negotiated car price or MSRP sticker price before discounts.

2

Enter down payment and trade-in

Include any cash down payment and the estimated trade-in value of your current vehicle.

3

Set the interest rate and loan term

Input your approved APR and choose term length (36, 48, 60, 72, or 84 months).

4

Review total cost breakdown

View monthly payment, total interest, and complete cost over the loan life.

True Cost of a Car

When buying a car, the sticker price isn't the final number. Trade-in values and down payments lower your principal, but sales tax and interest inflate it. This specific calculator handles all those variables distinctively compared to a standard home loan.

Why are auto loan terms getting longer?

Dealerships often push 72-month or 84-month loans to make the monthly payment look smaller to the buyer. However, cars are depreciating assets. A longer term means you will be "underwater" (owing more than the car is worth) for a significant portion of the loan, while paying thousands more in interest.

Frequently Asked Questions

Should I choose a 60 or 72-month loan term?

While a 72-month auto loan reduces your monthly payment, you will pay significantly more in total interest. Shorter loan terms generally offer lower interest rates and prevent you from owing more than the car is worth.

How does tax impact my car purchase?

Depending on your location, sales tax is applied to the final purchase price of the vehicle. However, in many jurisdictions, if you trade in a vehicle, the tax is only calculated on the difference between the new car price and the trade-in value.

Real-World Examples & Use Cases

New Car Budget Planning

Prospective car buyers should calculate the monthly payment BEFORE visiting the dealership to set a firm budget ceiling. Entering the target monthly payment and working backward (using different price points and terms) reveals the maximum car price you can afford. Knowing the true cost including interest prevents dealers from manipulating the transaction by focusing solely on monthly payments rather than the total transaction price and interest charges over the full loan term.

Trade-In Value Analysis

Trading in your current vehicle reduces the loan amount needed, potentially reducing both monthly payment and total interest. However, some dealers offer inflated trade-in values while marking up the new car price equally. Running the auto loan calculator with and without the trade-in, comparing against selling privately, reveals the true net value of dealer trade-in versus private sale. In most US states, trade-in credit also reduces the taxable sale amount, providing additional savings through avoided sales tax.

Loan Term Comparison

Auto loan terms increasingly stretch to 72 and 84 months as vehicle prices rise. A $35,000 car at 6% APR: 48 months = $822/month, $4,458 total interest; 72 months = $580/month, $6,797 total interest. The 72-month option saves $242/month but costs an extra $2,339 over the loan life. Adding 6+ years of depreciation risk (engine repairs, accident, etc.) makes the longer term substantially more expensive in real terms when all factors are considered.

Used Car vs New Car Analysis

Used cars typically carry higher auto loan interest rates (0.5-2% more) than new cars but have lower purchase prices. A new $28,000 car at 4.9% APR for 60 months = $528/month; $31,680 total cost. A comparable used $19,000 car at 6.4% APR for 60 months = $370/month; $22,200 total cost. The $9,480 total savings from buying used dramatically exceeds the higher interest rate cost. The auto loan calculator lets you make this comparison objectively with your specific numbers.

How It Works

Auto loan payments use the same amortization formula as mortgages: Monthly Payment (PMT): PMT = P × [r(1+r)^n] / [(1+r)^n - 1] Where: - P = Loan principal (car price - down payment - trade-in + sales tax) - r = Monthly interest rate (annual APR ÷ 12) - n = Total months (loan term × 12) Loan Principal = Car Price - Down Payment - Trade-In Value + Sales Tax Sales Tax typically applies to: Car Price - Trade-In (in most US states) Example: $30,000 car, $3,000 down, $5,000 trade-in, 7% APR, no sales tax: - Principal = 30,000 - 3,000 - 5,000 = $22,000 - Monthly payment at 7% / 60 months ≈ $436 - Total paid = $26,160; Total interest = $4,160

Frequently Asked Questions

What credit score do I need for a good auto loan rate?
Excellent credit (750+): 3-5% APR. Good credit (700-749): 5-7% APR. Fair credit (650-699): 8-12% APR. Poor credit (below 650): 12-20%+ APR. Improving your credit score before applying can save thousands over the loan life. A 5% vs 12% rate on a $25,000 loan over 5 years saves approximately $5,000 in total interest.
Should I make a large down payment on a car?
A 20% down payment is traditionally recommended. It reduces your loan amount, lowers monthly payments, reduces total interest, and helps prevent going underwater (owing more than the car's value). With new car depreciation averaging 15-25% in the first year, insufficient down payment means instant negative equity that could trap you in the loan.
What is negative equity on a car loan?
Negative equity (being underwater) means you owe more on the loan than the car is currently worth. This happens when depreciation outpaces your loan balance reduction — especially common with long-term loans. If you want to trade in or sell before payoff, you must cover the difference out of pocket or roll it into the next vehicle loan.
Should I use dealer financing or my own bank?
Always get pre-approved from your bank or credit union before visiting the dealership. Use this rate as your benchmark. Manufacturer-sponsored 0% APR deals are genuinely excellent if you qualify. Otherwise, dealers may mark up bank rates by 1-2% as profit. Having pre-approval creates competition and ensures you know the true market rate.
How does a trade-in affect my car loan?
Trade-in value directly reduces the loan principal needed. If your trade-in is worth $8,000 on a $30,000 car, you only borrow $22,000 (plus any down payment and taxes). In many US states, trade-in credit also reduces the taxable base, saving additional money on sales tax. Always know your car's value (Carmax, KBB, Carvana quotes) before negotiating at a dealership.
Disclaimer: The results provided by this calculator are estimates for informational and educational purposes only and do not constitute professional financial advice. Always consult with a qualified financial advisor before making any major financial decisions.

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