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Car Affordability Calculator – How Much Car Can You Afford?

Estimate a car payment and purchase-price ceiling after accounting for your existing debt, recurring vehicle costs, loan terms, and cash down.

How this car affordability calculator helps

This calculator estimates what a monthly loan payment could fit after recurring insurance, fuel, and maintenance costs are set aside. It then converts that payment into a financed amount and adds your down payment and trade-in value for a more useful shopping ceiling.

Formula: Available payment = max(0, 15% of gross monthly income − 35% of existing monthly debt − monthly insurance, fuel, and maintenance). The financed amount is the present value of that payment over the selected term and APR; the vehicle-price estimate adds your down payment and trade-in value.

Assumptions: The 15% and 35% factors are budgeting heuristics, not lender rules. Taxes, title, registration, dealer fees, and any remaining trade-in loan balance are not included. Enter realistic local ownership costs for a more conservative estimate.

Worked example: With $6,200 gross monthly income, $1,800 of existing debt, and $70 in monthly insurance, fuel, and maintenance, the budget model leaves up to $230 for a car payment. A $3,000 down payment and $2,000 trade-in value increase the estimated purchase-price ceiling by $5,000 over the financed amount.

  • Monthly income: Gross monthly household income before taxes.
  • Monthly debt: Existing loan and credit card obligations.
  • Ownership costs: Estimated monthly insurance, fuel, and maintenance before the loan payment.
  • Loan term: Number of years for the auto loan.
  • Interest rate: The APR for the new vehicle financing.
  • Cash at purchase: Down payment and trade-in value applied to the vehicle price.
  • Estimated vehicle price: Financed amount plus down payment and trade-in value, before taxes and fees.
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What the result means

The affordable payment is what remains after the entered recurring vehicle costs and the budget model's allowance for existing debt. The vehicle-price estimate then adds your down payment and trade-in equity to the amount that could be financed. It is a starting point for shopping, not a quote: taxes, title, registration, dealer fees, and negative equity can materially change the out-the-door price.

Related calculators

Budget planner for pairing a car payment with your full monthly spending plan, Loan calculator for modeling exact auto loan payments by price and term.

Frequently asked questions

  • Why enter insurance, fuel, and maintenance separately? They reduce the amount available for a loan payment, so a payment-only estimate does not hide the recurring costs of owning the vehicle.
  • Does the vehicle-price estimate include taxes and fees? No. The estimate includes only the financed amount, down payment, and net trade-in value entered. Add taxes, registration, title, dealer fees, and any trade-in payoff when comparing it with an out-the-door quote.

Last updated: 2026-10-03. This estimate is for budgeting and should be reviewed with your lender, insurer, and local vehicle costs.

Look beyond the monthly payment

A car payment that fits your budget on paper can still strain your finances once insurance, fuel, and maintenance are added in. A common guideline is the 20/4/10 rule: put at least 20% down, finance for no more than four years, and keep total transportation costs, including insurance, under 10% of your gross income.

Longer loan terms lower the monthly payment but increase total interest paid and raise the risk of owing more than the car is worth. If the affordable payment only works with a six or seven-year term, it's often a sign to consider a less expensive vehicle instead.

  • Get an insurance quote first: Premiums vary widely by model and can change what's actually affordable.
  • Budget for depreciation: New vehicles lose value fastest in the first few years, which matters if you plan to sell or trade in soon.
  • Leave a maintenance cushion: Set aside funds for tires, brakes, and routine service on top of the loan payment.

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