Car Affordability Calculator

What Is the Car Affordability Calculator?

This tool works backward from a monthly payment you can comfortably afford to calculate the maximum loan amount (and, adding your down payment, the maximum car price) that fits your budget, using the standard loan-payment formula solved for principal.

How to Use This Tool

Enter your monthly payment budget, loan term in months, expected interest rate, and down payment. Your maximum affordable car price appears instantly.

How the Maximum Price Is Derived

The calculator uses the present value of a stream of equal monthly payments. It converts your annual interest rate to a monthly rate by dividing by 100 and then by 12, and computes the largest loan a payment of your budget size could fully repay over the number of months you enter. It then adds your down payment to get the maximum car price. If you enter a 0 percent rate, the tool simply multiplies your monthly budget by the number of months.

A Worked Example With Hypothetical Numbers

With a 400 dollar monthly budget, a 60 month term, and a 6 percent annual rate, the monthly rate is 0.5 percent. The maximum loan comes out to roughly 20,700 dollars. Adding a 3,000 dollar down payment gives a maximum price near 23,700 dollars. Stretch the same 400 dollar payment to 72 months and the maximum loan grows, but you pay interest for a longer time. Raise the rate to 9 percent at 60 months and the maximum loan shrinks. The results are approximate and the exact values shown by the tool depend on the decimals you enter.

Why Term Length Deserves Caution

A longer term makes a bigger car fit within the same monthly payment, which is why it is tempting. But a longer loan means more total interest, and the balance may stay higher than the car's value for longer, a situation sometimes called being underwater. That can make it harder to sell or trade in the vehicle. A useful test is to run the calculator at several terms and compare not only the maximum price but also how long you would be making payments on something that is aging and losing value.

Building a Realistic Monthly Budget

• The payment budget you enter should be just the loan payment. Set aside separate amounts for insurance, fuel, maintenance, and registration, which can add up to a significant monthly total.
• Some households use a rule of thumb to limit total vehicle costs to a share of income. Any such percentage is a personal guideline, not a rule, so choose one that suits your situation.
• Use a realistic interest rate. Pre-qualification or preapproval from a bank or credit union will give a more honest number than a guess.

What the Number Does Not Include

• Sales tax, title, registration, and dealer fees, which may be paid up front or rolled into the loan. If you finance them, they reduce the vehicle price you can afford.
• Trade-in value, which you can add to the down payment field if you want to include it.
• Insurance premiums, which vary by vehicle and driver.
• Any negative equity carried over from a prior loan.

Common Mistakes

• Entering the term in years instead of months. Five years is 60 months.
• Using the maximum result as a shopping target. Aim below it to leave room for taxes and fees.
• Ignoring how the rate differs for used versus new vehicles, or for different credit profiles.

For personalized advice, consider talking with a credit union or a nonprofit credit counselor, especially if your budget is tight.

Frequently Asked Questions