Auto Loan Payment Calculator
Calculate your monthly auto loan payment, total interest cost, and total amount paid. Enter the vehicle price, your down payment, loan term in months, and annual interest rate (APR). The calculator uses the standard amortising loan formula required to be disclosed under the federal Truth in Lending Act. You can adjust any input to compare different loan scenarios before visiting a dealer.
Auto loan amortisation formula
P = Vehicle_price - Down_payment
r = Annual_rate / 12 / 100
n = Loan_term_months
Monthly payment M = P x [r x (1+r)^n] / [(1+r)^n - 1]
Total paid = M x n
Total interest = Total_paid - P
This is the standard fixed-rate amortising loan formula. It is the basis for the payment schedules that lenders must disclose under the federal Truth in Lending Act (TILA, Regulation Z, 12 CFR Part 1026).
How loan term affects total interest paid
- 36 months: higher monthly payment, lowest total interest, fastest to own the vehicle outright.
- 48 months: moderate balance between payment and total cost.
- 60 months: the most common term in the US; balances affordability and total cost.
- 72 months: lower monthly payment but substantially more interest paid over the life of the loan.
- 84 months: the lowest monthly payment but the highest total interest and highest risk of negative equity, as the vehicle depreciates faster than the loan is paid down.
Auto loan calculator: frequently asked questions
How is a monthly auto loan payment calculated?
The standard amortizing loan formula is: M = P x [r(1+r)^n] / [(1+r)^n - 1], where P is the principal (vehicle price minus down payment), r is the monthly interest rate (annual rate / 12), and n is the number of monthly payments. This is the same formula used by banks and the Consumer Financial Protection Bureau.
What is a good interest rate for an auto loan?
The Federal Reserve's G.19 Consumer Credit report tracks average auto loan rates. As of early 2026, average rates for new vehicles were approximately 6 to 8% APR for borrowers with good credit, and used vehicle rates were typically 1 to 3 percentage points higher. Your rate depends on credit score, loan term, lender type, and whether the vehicle is new or used.
Does loan term length affect total cost significantly?
Yes, substantially. A 60-month loan at 7% APR on a $30,000 vehicle results in about $5,600 in total interest. The same loan at 84 months results in about $7,900 in total interest. Longer terms lower the monthly payment but significantly increase total cost. The CFPB warns that 84-month or longer terms can lead to negative equity (owing more than the car is worth).
What is the difference between APR and interest rate on a car loan?
The interest rate is the cost of borrowing the principal. The APR (Annual Percentage Rate) includes the interest rate plus any fees (origination fees, documentation fees) rolled into the financing cost. Under the federal Truth in Lending Act (TILA, 15 U.S.C. 1601), lenders must disclose the APR. Always compare APR, not just interest rate, when shopping loan offers.
Should I put more money down on a car?
A larger down payment reduces your loan principal, which lowers both the monthly payment and total interest paid. It also helps you avoid negative equity. The CFPB generally recommends a down payment of at least 20% on a new vehicle and 10% on a used vehicle to account for immediate depreciation after purchase.
Official sources
- CFPB Auto Loans: consumerfinance.gov/consumer-tools/auto-loans.
- Federal Reserve G.19 Consumer Credit: federalreserve.gov/releases/g19.
Reviewed by the CalculatorHub team, edited by James Graham, 14 June 2026. See our methodology.