Calculate monthly auto loan payments, trade-in equity, interest rate, sales taxes, and total vehicle cost.
Configurable Calculation Inputs
Vehicle Purchase Price: number (Default: 35000 $)
Cash Down Payment: number (Default: 5000 $)
Trade-in Value / Equity: number (Default: 3000 $)
Loan Term (Months): select (Default: 60)
Interest Rate (APR %): number (Default: 5.9 %)
Sales Tax Rate (%): number (Default: 6.5 %)
Mathematical Formula: Auto Financing Monthly Payment
Payment = (Loan Amount * r) / (1 - (1 + r)^-n)
Where Loan Amount is Car Price minus Down Payment and Trade-In equity, plus Sales Tax and Fees.
Comprehensive Guide & Context
Why Longer Loan Terms Cost More
While a 72 or 84-month loan lowers your monthly installment, it drastically increases the total cumulative interest paid and risks putting you underwater on your vehicle equity.
Worked Calculation Examples
New SUV Purchase (60 Months)
$42,000 vehicle with $7,000 down at 5.5% APR for 5 years.
Result: $676 / month
Frequently Asked Questions
What is the 20/4/10 rule for car buying?
Put at least 20% down, finance for no longer than 4 years (48 months), and ensure total vehicle expenses (payment + insurance) stay under 10% of gross monthly income.