Auto Loan Calculator
Estimate your monthly car payment, total interest, and sales tax for any vehicle price, down payment, and loan term.
Monthly payment
$489.15
60-month loan at 6.5%
Total interest paid
$4,349
Total cost of loan
$34,349
Amount financed
$25,000
Sales tax
$0
Select a state to estimate sales tax
Loan cost breakdown
Compare loan terms
See how a 72-month term compares to your selected 60-month term.
60 months
- Monthly payment
- $489.15
- Total interest
- $4,349
- Total cost
- $34,349
72 months
- Monthly payment
- $420.25
- Total interest
- $5,258
- Total cost
- $35,258
You pay $909 more in interest with the 72-month term, in exchange for a $68.91 lower monthly payment than the 60-month term.
Show the math
Your amount financed starts with the vehicle price, subtracts your down payment and trade-in value, then adds any sales tax rolled into the loan.
Amount financed = $30,000 − $5,000 − $0 + $0 = $25,000
Lenders then use the standard amortizing-loan formula so every payment is the same size, even though the mix of principal and interest inside each payment changes over time.
M = P × [r(1 + r)n] / [(1 + r)n − 1]
With your numbers, P (amount financed) = $25,000, r (monthly rate) = 0.5417% (that's 6.5% ÷ 12), and n (number of payments) = 60.
M = $25,000 × [0.005417 × (1 + 0.005417)60] / [(1 + 0.005417)60 − 1] = $489.15
In plain English: P is the amount financed (what you still owe after your down payment, trade-in, and sales tax are accounted for), r is your monthly interest rate, and n is the number of monthly payments over your loan term. Your balance grows by a factor of about 1.3828× over the life of the loan if no payments were made — the formula backs out the fixed payment size that exactly cancels that growth over 60 months.