Car Affordability Calculator
Turn a monthly payment budget into the car price you can afford, with down payment, trade-in and payoff, sales tax, fees and rebates — plus out-the-door cost, cash due at signing, price by loan term and an amortization schedule.
How it works
Max loan = payment × (1 − (1 + i)^−n) ÷ i · Car price = (max loan + down + rebate + trade-in equity − fees + tax rate × trade-in credit) ÷ (1 + tax rate) when tax and fees are in the loan · Car price = max loan + down + rebate + trade-in equity when you pay them in cash · i = APR ÷ 12, n = months
This runs the loan formula backwards: instead of finding the payment from a price, it finds the largest loan a fixed monthly payment can repay, then works out the sticker price that loan buys. The down payment, any rebate and any trade-in equity (trade-in value minus what you still owe on it) are added on top. If you choose to put sales tax and fees in the loan, part of the loan pays for them, so the price is divided by one plus the tax rate after the fees are taken out; if you pay them in cash at signing, the whole loan goes toward the car and the extra cash is shown separately. In most US states the trade-in value is subtracted before sales tax is charged, which you can switch off under More options. Negative equity on a trade-in is added to the loan, which lowers the price you can afford. The tables show how the price changes with the loan term and with your monthly budget, and how the loan is paid down year by year. To start from your income instead of a payment, use the car affordability by income calculator.
Worked example
A $400 monthly budget at 7.5% over 60 months supports a loan of about $19,962. With $3,000 down, $500 of fees and 6% sales tax rolled into the loan, the car can cost up to about ($19,962 + $3,000 − $500) ÷ 1.06 ≈ $21,191, plus $1,271 of tax — $22,962 out the door. You would pay $24,000 over the loan, $4,038 of it interest. Paying the tax and fees in cash instead lets the same budget buy a $22,962 car, but you need $3,000 + $1,378 + $500 = $4,878 at signing.
Sources: CFPB — Auto loans: key terms and what to know before you buy
Frequently asked questions
How much of my income should go to a car payment?
A widely used rule keeps the payment at 10–15% of monthly take-home pay, and total car costs (payment, insurance, fuel, upkeep) under about 20%. The calculator shows the take-home pay range your payment suits. For a full income-based check with your other debts, use the car affordability by income calculator.
Does a longer term let me afford more car?
It raises the price a given payment supports, as the term table shows, but you pay much more interest and stay underwater — owing more than the car is worth — for longer. 60 months or less is the usual guidance.
Should I put the sales tax and fees in the loan?
Rolling them in keeps the cash you need at signing low, but you pay interest on them and less of the loan goes toward the car. Paying them in cash lets the same monthly budget buy a more expensive car, at the cost of more money up front. Switch the option to compare both.
How does a trade-in change what I can afford?
Positive equity (the trade-in is worth more than you owe) works like extra down payment, and in most states it also lowers the sales tax. If you owe more than the car is worth, the difference is added to the new loan, so less of your budget goes toward the new car.
Does my credit score matter?
Yes. The rate sets how big a loan a payment supports: at $400 a month for 60 months, 5% supports about $21,200 while 12% supports about $18,000. Get pre-approved so you know your real rate before you shop.
Related calculators
Educational estimate, not financial advice — dealer terms, fees and taxes vary.