This calculator estimates your fixed monthly car payment using the standard loan amortization formula. Enter the total loan amount (vehicle price minus any down payment or trade-in value), the annual interest rate from your lender, and the loan term in months.
The formula used is: M = P × r(1+r)^n / ((1+r)^n − 1), where P is the loan principal, r is the monthly interest rate (annual rate ÷ 12), and n is the number of monthly payments.
Auto loan terms typically range from 24 to 84 months. Shorter terms mean higher monthly payments but less total interest paid. Longer terms lower your monthly payment but increase the overall cost of the loan.
Suppose you're financing a $25,000 used car with a $3,000 down payment, leaving a loan amount of $22,000. Your lender offers a 6% annual interest rate over a 60-month term.
The monthly rate is 6% ÷ 12 = 0.5%. Using the amortization formula, your monthly payment would be approximately $424.94. Over 60 months you'd repay a total of $25,496 — meaning about $3,496 in interest over the life of the loan.
If you extended the same loan to 72 months, the monthly payment would drop to roughly $365.45, but total interest paid would rise to around $4,312 — an extra $816 just for the longer term. This is why it's worth running both scenarios before committing to a loan offer.
No. This calculator covers principal and interest only. When buying a car, your actual financed amount may also include sales tax, dealer fees, registration costs, and optional add-ons like extended warranties or GAP insurance. Always ask your dealer for an out-the-door price and finance the full amount including any rolled-in costs to get an accurate monthly payment estimate.
Auto loan rates vary based on your credit score, the age of the vehicle, the lender, and broader economic conditions. Generally, new car loans carry lower rates than used car loans. Borrowers with excellent credit (720+) typically qualify for the most competitive rates. Credit unions often offer lower rates than dealership financing, so it's worth getting pre-approved before visiting a dealer.
A larger down payment directly reduces the principal you need to finance, which lowers both your monthly payment and the total interest paid. It can also help you avoid being "underwater" on the loan — owing more than the car is worth — which is a common risk with long-term auto loans on depreciating vehicles. Aim for at least 10–20% down when possible.
The most common auto loan terms are 48, 60, and 72 months. A 48-month loan has the highest monthly payment but the lowest total cost. A 72-month loan is easier on monthly cash flow but costs significantly more in total interest and increases the risk of negative equity as the car depreciates. As a rule of thumb, try not to finance a vehicle for longer than you plan to own it.
Yes — just change the term field and hit Calculate again to compare scenarios side by side. Try running 48, 60, and 72 months with the same principal and rate to see how the monthly payment and total cost change with each option.
The most effective ways are: increase your down payment to reduce the loan principal; negotiate a lower purchase price on the vehicle; shop around for a better interest rate through a bank or credit union before visiting the dealership; or extend the loan term. Keep in mind that extending the term trades lower monthly payments for higher total cost, so weigh both factors carefully.