Before You Go to the Dealership, Run These Numbers
Most people walk into a car dealership with a vague budget in their head. Dealers know this. The moment you say "I can do around $500 a month," you've handed them control of the deal. This calculator puts the numbers in your hands first.
Use the out-the-door price, not the sticker
The vehicle price field should have the real number — after taxes, destination charges, and dealer fees. The sticker price almost never matches what you actually pay. Ask the dealer for a written out-the-door quote before running any calculations, otherwise your estimate will be off by $1,500 to $3,000.
Your interest rate matters more than most people realize
A 2% difference in APR on a $30,000 loan over 60 months works out to roughly $1,600 extra in interest. That's not nothing. Before accepting the rate a dealership offers, check what your own bank or credit union will give you — it's often noticeably lower. Get pre-approved first, then use that number as leverage at the dealership.
The monthly payment trap
If a salesperson says "we can get you into this car for $399 a month" — stop and run the full numbers. $399 × 84 months = $33,516. On a $28,000 car. That's over $5,500 in interest, and you're tied to the loan for 7 years on a car that'll be worth maybe $12,000 by the end. Always look at total cost, not just the monthly number.
Longer loan = lower payment, but you pay for it
The jump from 60 to 72 months on a $32,000 loan at 7% drops your monthly payment by about $60. Sounds appealing. But you pay roughly $900 more in interest and you're still making payments on a 6-year-old car when most people are ready to move on. The 48–60 month range is generally the sweet spot.
How the math works
The calculator uses standard amortization: M = P × [r(1+r)^n] / [(1+r)^n – 1]. P is your loan amount (price minus down payment), r is your monthly rate (annual rate ÷ 12), and n is number of months. Early payments go mostly to interest. Later ones go mostly to principal. The amortization schedule shows exactly how that split changes — useful if you're thinking about making extra principal payments to pay off the loan faster.
