Rex says
Money math without the spreadsheet headache. Plug in your numbers and I'll show you exactly where the dollars land.
Try a scenario
Click to load — tweak from there.Inputs
Result
Car price you can afford
$30,131
Affordable loan payment
$500.00
Amount you can finance
$25,131
Total monthly car budget
$780.00
Interest over the loan
$4,869
Total spend over the term
$46,800
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One click, a permanent link with your numbers baked in.
How to use this
- 1Enter gross monthly income ($).
- 2Enter share of income for the payment (%).
- 3Enter down payment + trade-in ($).
- 4Enter loan apr (%).
- 5Enter loan term (months).
- 6Enter monthly insurance + fuel ($).
- 7Read your car price you can afford on the right — it updates as you type.
- 8Hit Share to keep the scenario or send it to someone.
About this calculator
The common rule is 20/4/10: 20% down, a four-year loan, and total vehicle costs under 10% of gross income. Insurance and fuel are what break most budgets, not the payment itself.
Worked example
Using the values the calculator loads with:
Inputs
- Gross monthly income: 6500 $
- Share of income for the payment: 12 %
- Down payment + trade-in: 5000 $
- Loan APR: 7.2 %
- Loan term (months): 60
- Monthly insurance + fuel: 280 $
Results
- Car price you can afford: $30,131.07
- Affordable loan payment: $500.00
- Amount you can finance: $25,131.07
- Total monthly car budget: $780.00
- Interest over the loan: $4,868.93
- Total spend over the term: $46,800.00
What each field means
Inputs
- Gross monthly income ($)
- The gross monthly income used in the calculation, measured in $. Starts at 6500 $ so you have a working example on load.
- Share of income for the payment (%)
- The share of income for the payment used in the calculation, measured in %. Starts at 12 % so you have a working example on load. Accepted range: 1–40 %.
- Down payment + trade-in ($)
- The down payment + trade-in used in the calculation, measured in $. Starts at 5000 $ so you have a working example on load.
- Loan APR (%)
- The loan apr used in the calculation, measured in %. Starts at 7.2 % so you have a working example on load.
- Loan term (months)
- The loan term (months) used in the calculation. Starts at 60 so you have a working example on load. Accepted range: 12–96.
- Monthly insurance + fuel ($)
- The monthly insurance + fuel used in the calculation, measured in $. Starts at 280 $ so you have a working example on load.
Results
- Car price you can afford
- Returned as a money amount in US dollars and shown as the headline result. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Affordable loan payment
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Amount you can finance
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Total monthly car budget
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Interest over the loan
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Total spend over the term
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
FAQ
How does the car affordability calculator work?
The common rule is 20/4/10: 20% down, a four-year loan, and total vehicle costs under 10% of gross income. Insurance and fuel are what break most budgets, not the payment itself. The underlying maths is: Affordable price = Down payment + PV of (target payment) over the loan term.
What do I need to enter?
6 values: gross monthly income, share of income for the payment, down payment + trade-in, loan apr, loan term (months), and monthly insurance + fuel. Each field starts with a sensible default, so you can change one number at a time and watch the result move.
What does the car price you can afford result mean?
It is returned as a money amount in US dollars and updates live as you edit the inputs, so you can compare two or three versions of a scenario in a few seconds.
Is this calculator free, and do I need an account?
Yes, it's free, and no account is required. Nothing you type is stored on our servers — the maths runs entirely in your browser.
How accurate is the result?
It applies the standard formula exactly, so the arithmetic is precise. Results are estimates before tax, fees, and inflation unless an input explicitly covers them.
Who is this tool for?
It's built for anyone comparing money scenarios before committing — budgeting a payment, sanity-checking a quote, or seeing what a change in rate or term actually costs.
Accuracy and limitations
- Results are estimates before tax, fees, and inflation unless an input explicitly covers them.
- Rates are treated as fixed for the whole period — variable-rate products will drift from this projection.
- This is educational maths, not financial advice. Check anything contractual with the lender or your accountant.
Related tools
Cite this calculator
Writing about this topic? Grab a citation — every link helps keep these tools free.
RevenueLab. (2026). Car Affordability Calculator. Retrieved from https://www.revenuelab.fyi/toolbox/car-affordability-calculator
<p>Source: <a href="https://www.revenuelab.fyi/toolbox/car-affordability-calculator" target="_blank" rel="noopener">Car Affordability Calculator — RevenueLab</a> (2026).</p>
Source: [Car Affordability Calculator — RevenueLab](https://www.revenuelab.fyi/toolbox/car-affordability-calculator) (2026).