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
Affordable car price
$26,618
Loan amount
$22,618
Total interest
$4,382
Total of payments
$27,000
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One click, a permanent link with your numbers baked in.
How to use this
- 1Enter comfortable monthly payment ($).
- 2Enter apr (%).
- 3Enter term (months).
- 4Enter down payment + trade-in ($).
- 5Read your affordable car price on the right — it updates as you type.
- 6Hit Share to keep the scenario or send it to someone.
About this calculator
Work backwards from a comfortable monthly payment to a purchase price, including your trade-in and down payment. The widely used guardrail is keeping total car costs under 15% of take-home pay.
Worked example
Using the values the calculator loads with:
Inputs
- Comfortable monthly payment: 450 $
- APR: 7.2 %
- Term: 60 months
- Down payment + trade-in: 4000 $
Results
- Affordable car price: $26,617.96
- Loan amount: $22,617.96
- Total interest: $4,382.04
- Total of payments: $27,000.00
What each field means
Inputs
- Comfortable monthly payment ($)
- The comfortable monthly payment used in the calculation, measured in $. Starts at 450 $ so you have a working example on load.
- APR (%)
- The apr used in the calculation, measured in %. Starts at 7.2 % so you have a working example on load.
- Term (months)
- The term used in the calculation, measured in months. Starts at 60 months so you have a working example on load.
- Down payment + trade-in ($)
- The down payment + trade-in used in the calculation, measured in $. Starts at 4000 $ so you have a working example on load.
Results
- Affordable car price
- 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.
- Loan amount
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Total interest
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Total of payments
- 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?
Work backwards from a comfortable monthly payment to a purchase price, including your trade-in and down payment. The widely used guardrail is keeping total car costs under 15% of take-home pay. The underlying maths is: Loan capacity is back-solved from the payment, then price = loan + down payment + trade-in.
What do I need to enter?
4 values: comfortable monthly payment, apr, term, and down payment + trade-in. Each field starts with a sensible default, so you can change one number at a time and watch the result move.
What does the affordable car price 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
<p>Source: <a href="https://www.revenuelab.fyi/toolbox/car-affordability" target="_blank" rel="noopener">Car Affordability Calculator — RevenueLab</a> (2026).</p>
Source: [Car Affordability Calculator — RevenueLab](https://www.revenuelab.fyi/toolbox/car-affordability) (2026).