Car Loan Calculator: True Cost of Financing a Vehicle

A car is often the second-largest purchase people make. Understanding the true cost — beyond just the sticker price — helps you negotiate better and budget accurately.

What goes into your car payment

Amount Financed = Vehicle Price – Trade-In – Down Payment + Sales Tax
Monthly Payment = Amount Financed × [r(1+r)^n] / [(1+r)^n – 1]

Example: $35,000 car, $5,000 down, $3,000 trade-in, 7% tax, 5.9% rate, 60 months:

• Net price: $35,000 – $3,000 = $32,000
• Tax: $32,000 × 7% = $2,240
• Amount financed: $32,000 + $2,240 – $5,000 = $29,240
• Monthly payment: $563.71
• Total interest: $4,582
• Total cost: $35,000 + $2,240 + $4,582 = $41,822

The trade-in advantage

A trade-in reduces your loan principal directly. In many states, you only pay sales tax on the difference (price minus trade-in), saving even more.

$3,000 trade-in on a $35,000 car:

• Reduces financed amount by $3,000
• Saves ~$210 in tax (at 7%)
• Saves ~$470 in interest over 60 months

Loan term comparison

Term	Monthly	Total Interest	Total Cost
36 months	$879	$2,404	$37,404
48 months	$672	$3,203	$38,203
60 months	$551	$3,857	$38,857
72 months	$471	$4,653	$39,653

Each 12 months added saves ~$100-200/month but costs $600-800 more total.

True monthly cost of ownership

Your car payment is only part of the monthly cost:

• Loan payment: $564
• Insurance: $150–250
• Fuel: $150–300
• Maintenance: $50–100
• Total: $900–1,200/month

Cash vs finance decision

Factor	Pay Cash	Finance
Total cost	Lower	Higher (interest)
Opportunity cost	High (lost investment gains)	Low
Monthly cashflow	$0/month after	$500+/month for years
Negotiating power	Stronger (dealers prefer cash-ready buyers)	Standard

If your investments earn more than the loan rate, financing can be mathematically better.

Calculate your car payment with our Car Loan Calculator — includes trade-in, tax, and total ownership cost breakdown.