Car affordability

How Much Car Can I Afford?

Stop guessing from the sticker price. This calculator starts from your take-home pay and the 20/4/10 rule, subtracts insurance and fuel, and tells you the real maximum car price.

A worked example

Say you take home $4,500 a month and use the moderate 15% rule. That gives a total car budget of $675/month for everything. Insurance and fuel run about $250/month, so $425 is left for the loan payment. At a 7.5% APR over 60 months, $425/month supports a loan of roughly $21,200. Add a $3,000 down payment and your maximum car price is about $24,200— quite different from what a dealer's "you're approved for $40,000" suggests.

The lesson: affordability is set by your monthly budget working backward, not by the loan amount a lender is willing to approve. Approval tells you the most you can borrow; this tells you the most you should.

The 20/4/10 rule, explained

The 20/4/10 rule is the most durable rule of thumb in car buying because each number guards against a specific trap:

20% down — a new car loses value the moment you drive off the lot. A fifth down keeps you from owing more than the car is worth in year one.
4-year term — financing for 48 months or less keeps total interest in check and means you own the car outright while it still has years of life left.
10% of income — capping all vehicle costs (payment, insurance, fuel, maintenance) at 10% leaves room for the rest of your budget and emergencies.

The calculator lets you relax the income share to 15% or 20% if your situation allows, but it always subtracts running costs first — because that's the part people forget.

Common mistakes that wreck a car budget

Financing for 72–84 months.The low monthly payment hides thousands in extra interest and years of negative equity. If you need that long a term to afford it, you can't afford it.
Ignoring insurance and fuel. A sporty or luxury car can cost twice as much to insure. Budgeting only for the loan payment is how people end up house-poor on wheels.
Rolling negative equity forward. Trading in a car you still owe money on, and adding that balance to the new loan, starts you underwater on day one.
Shopping by monthly payment. Dealers can hit almost any monthly target by stretching the term. Negotiate the out-the-door price, then check the term.

Car affordability FAQ

How much car can I afford on my salary?: A common guideline is to keep all car costs — loan payment, insurance, and fuel — under 10–15% of your monthly take-home pay. On $4,500 take-home, that's $450–$675 a month for everything. After subtracting insurance and fuel, what's left supports the loan payment, which sets your max price. The calculator above does this math for you.
What is the 20/4/10 rule?: It's a simple car-buying budget: put at least 20% down, finance for no more than 4 years (48 months), and keep total monthly vehicle costs at or below 10% of your gross income. It's deliberately conservative — it keeps you from being underwater on the loan and protects against surprise repair or insurance costs.
Should I include insurance and fuel in my car budget?: Yes — and most calculators don't, which is why they overestimate. Insurance, fuel, and maintenance are real monthly costs that compete with the loan payment for the same budget. A $500/month budget with $250 of insurance and fuel leaves only $250 for the loan, not $500.
Is a longer loan term a good idea to afford more car?: Usually not. Stretching to 72 or 84 months lowers the monthly payment but you pay far more interest and stay 'underwater' (owing more than the car is worth) for years. If you can only afford the car at 84 months, the honest answer is that you can't really afford that car.
How much should I put down on a car?: At least 20% on a new car and 10% on a used one is the standard advice. A larger down payment shrinks the loan, reduces total interest, and protects you from negative equity if the car depreciates faster than you pay it down.
Does this include taxes and registration?: This calculator focuses on the price you can support from your monthly budget. Sales tax, title, registration, and dealer fees are paid on top — use the Auto Loan Calculator to layer those in once you have a target price.

Keep going

Once you have a target price, layer in tax and fees with the Auto Loan Calculator, compare it to a personal loan, check what's left after tax with the Salary Calculator, or see how a car payment fits your debt payoff plan. New to the terms? Read up on APR and principal.

This tool is for educational purposes only and is not a loan offer or financial advice.