Use our Auto Loan Calculator to estimate your monthly car payment, total interest, and the true amount you’ll finance after taxes, fees, trade-in, and down payment. See how a small extra monthly payment can shorten your term and save you money.
Why use an Auto Loan Calculator?
Buying a car involves more than the sticker price. Sales tax, title and registration fees, dealer charges, your down payment, and trade-in equity all affect the amount you actually finance. Our Auto Loan Calculator brings these pieces together so you can compare offers and budget confidently before you visit the dealership.
How to use the Auto Loan Calculator
- Enter the vehicle price (the negotiated purchase price).
- Add your down payment and any trade-in value. If you still owe on your trade, include the payoff amount.
- Enter your local sales tax rate and any title/registration/dealer fees.
- Provide the APR (annual percentage rate) and the loan term in months.
- Optionally, add an extra monthly payment to see payoff acceleration and interest savings.
What your results show
- Amount financed: The principal after applying tax, fees, down payment, and trade-in equity.
- Monthly payment: Your estimated payment based on APR and term.
- Total interest: The interest you’ll pay over the life of the loan.
- Total of payments: Principal plus interest paid to the lender.
- With extra payment: Estimated months to payoff and interest savings if you pay extra each month.
How the calculation works
The amount you finance typically equals: vehicle price + fees + sales tax ? down payment ? trade-in value + any trade-in payoff you still owe. In many regions, sales tax is applied to the price after subtracting the trade-in value, but rules vary by state or country. The calculator uses that common approach.
Monthly payments for a fixed-rate auto loan use the standard amortization formula: Payment = Principal × r ÷ (1 ? (1 + r)?n), where r is the monthly interest rate (APR ÷ 12) and n is the number of months. When APR is 0%, the payment is simply Principal ÷ n.
Tips to lower your car payment
- Increase your down payment to reduce the amount financed.
- Provide a trade-in with positive equity, or pay off any negative equity first.
- Shop multiple lenders for the best APR; even a small rate drop can save hundreds.
- Choose a slightly longer term for a lower payment, but note total interest may rise.
- Make a small extra monthly payment to shorten your term and cut interest costs.
Understanding taxes and fees
Sales tax rates and what’s included in the taxable amount differ by location. Many places let you subtract your trade-in value from the purchase price before tax. Fees can include title, registration, documentation, and dealer charges. While some fees are fixed, others are negotiable—be sure to ask for a breakdown.
Comparing offers the smart way
Use the Auto Loan Calculator to compare loan terms (36 vs 60 months), different APRs, or the effect of a bigger down payment. Try scenarios like adding $25–$100 as an extra monthly payment; you’ll often see a significant cut in total interest and months to payoff, which can keep you from being underwater if you sell or trade the car later.
What to do before you finance
- Check your credit and correct any errors to qualify for better rates.
- Get preapproved so you know your rate range before negotiating.
- Negotiate the vehicle price separately from financing and trade-in.
- Read the contract carefully for add-ons and prepayment rules.
Armed with accurate numbers from the Auto Loan Calculator, you’re ready to choose the loan that fits your budget and long-term goals.