Car Affordability Calculator
How much car can you afford? Enter your income, debts, down payment, and expected rate. We apply the 20/4/10 rule and check your debt-to-income ratios, then solve for the maximum car price — including insurance and gas.
Your car-buying budget
How it works
The 20/4/10 rule is the starting point: put at least 20% down, finance for 4 years (48 months) or less, and keep total monthly car costs — loan payment, insurance, and gas or charging — at or below 10% of your gross monthly income. The 20% down payment matters because a new car typically loses roughly 15–20% of its value in the first year; without it, you can end up owing more than the car is worth.
On top of the 20/4/10 rule, this calculator checks your debt-to-income (DTI) ratio — your total monthly debt payments divided by your gross monthly income. Lenders generally like to see total DTI at or below about 36%, though some auto lenders allow more. The calculator takes the lower of the two budgets (the 10% car-cost cap and the DTI cap) and works backward to a car price at your rate and term.
Watch which limit binds: if the back-end DTI is the limiting factor, paying off a credit card or a small loan can raise your budget more than saving a few thousand extra for the down payment. The results show both figures so you can see exactly where you stand.
Frequently asked questions
What is the 20/4/10 rule?
It is the car-buying guideline most experts recommend: put at least 20% down, keep the loan term to 4 years (48 months) or less, and keep total monthly car costs — loan payment, insurance, and gas or charging — at or below 10% of your gross monthly income.
What counts as monthly debt in the DTI calculation?
Student loans, credit-card minimum payments, personal loans, and child support count. Utilities, groceries, subscriptions, and income taxes do not.
Does the calculator include insurance and gas?
Yes. The maximum car price is solved from your full monthly car budget, including the loan payment plus insurance and gas or charging — so the number you see is the whole cost, not just the payment.
Why is my affordable price lower than what a dealer pre-approved?
Pre-approvals often stretch to the maximum a lender will allow, sometimes with longer terms of 72 or 84 months. This calculator uses the conservative 20/4/10 guideline so the payment fits your budget comfortably, not just barely.
How can I increase how much car I can afford?
The three biggest levers are: pay down monthly debts (helps the back-end DTI), save a larger down payment (lowers the loan and keeps you from going upside down), and improve your credit score to qualify for a lower interest rate.
Is the result a guarantee I can get a loan?
No. This is an estimate based on the 20/4/10 rule and standard DTI math. Actual approval depends on your credit score, employment history, the loan program, and the lender's full underwriting.
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