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Car Affordability Calculator

Tell us the monthly payment you're comfortable with, your down payment, the interest rate, and the term, and we'll work backward to the maximum car price that fits your budget.

Maximum car price you can afford
$0
Amount you can finance$0
Total interest paid$0
Payment % of income0%
10% income target$0
Tools · By Mustafa Bilgic · Last updated 20 June 2026

How affordability is calculated

Most car shoppers start with a monthly payment in mind. This calculator runs the loan math in reverse: it takes the payment you can comfortably make and the loan terms, solves for the loan balance that payment supports, then adds your down payment and trade-in and backs out sales tax to find the sticker price you can afford. The loan side uses the standard amortization formula, so the figure matches what a lender would quote for the same payment, rate, and term.

Because the result depends heavily on the term, we also show your payment as a percentage of gross income and a 10% total-transportation target, so a low payment on an 84-month loan does not trick you into "affording" a car you cannot actually run.

Worked example: A $450/month payment at 6.5% APR over 60 months supports a loan of about $22,990. Add a $4,000 down payment for roughly $26,990 financed-plus-cash, then back out 7% tax to land near a $25,200 car price. The $450 payment is 8.2% of a $5,500 monthly income — inside the 10% guideline.

The 20/4/10 rule of thumb

A long-standing affordability guideline is the 20/4/10 rule: put at least 20% down, finance for no more than 4 years, and keep total transportation costs (payment, insurance, and fuel) under 10% of gross monthly income. The down payment protects you from negative equity during the steep first-year depreciation, the short term limits total interest, and the 10% ceiling leaves room for the running costs a payment alone hides. This calculator lets you stretch beyond the rule, but the income-percentage readout shows you when you are doing it.

Affordable to buy is not affordable to own. Insurance, fuel, and maintenance can add $300–$600 a month. Check those first with the cost per mile calculator and fuel cost calculator.

Use it with our other buying tools

Once you know your target price, confirm the payment with the car loan calculator, compare financing against leasing in the lease vs buy calculator, and weigh the long-term picture with the total cost of ownership calculator. New buyers should also read how to buy a used car and how to negotiate car price.

Frequently asked questions

What is the 20/4/10 rule for buying a car?

The 20/4/10 rule is a simple affordability guideline: put at least 20 percent down, finance for no more than 4 years (48 months), and keep total monthly transportation costs, including the loan payment, insurance, and fuel, under 10 percent of your gross monthly income. Following it keeps you from being upside down on the loan and leaves room in your budget for the running costs a car payment alone ignores.

Should I base my budget on the monthly payment or the total price?

Shop by total price, not by monthly payment. Dealers can hit almost any monthly number by stretching the term to 72 or 84 months, which quietly raises the total you pay and keeps you in negative equity for years. Decide the most you will spend overall, use a payment you can comfortably afford on a 48 to 60 month term, and walk away from a longer loan dressed up as a lower payment.

Does this calculator include insurance and fuel?

The main result is the vehicle price your loan payment supports, but the page also shows a 10 percent total-transportation target so you can sanity-check the loan against insurance, fuel, and maintenance. A payment you can technically make is not affordable if it leaves nothing for the running costs. Use our cost per mile and fuel cost calculators to estimate those before you commit.