How WhatCarFits Calculates Affordability
WhatCarFits starts with the monthly payment you want to stay around, then works backward to estimate a vehicle price range. This page explains the assumptions behind that estimate and why your actual financing offer may be different.
Start With the Payment. Work Back to the Car.
Rather than choosing a vehicle first and calculating the payment afterward, WhatCarFits uses your budget to estimate the amount of vehicle that may fit.
What Goes Into the Estimate
The estimate changes based on the information you provide. Some inputs affect how much can be financed, while others change the amount that needs to be financed.
Monthly Payment
This is the payment you tell us you want to stay around. It is the starting point for the affordability calculation.
Credit Score
Your entered score helps us select an estimated APR range. It does not trigger a credit check and is not a lender decision.
Loan Term
A longer term can lower the estimated monthly payment but may increase the total interest paid over the life of the loan.
Down Payment
Cash paid at purchase reduces the amount that would need to be financed.
Trade-In Value
An entered trade-in value is treated as additional value applied toward the transaction.
Taxes and Fees
Estimated taxes and transaction costs are considered because the amount financed can be higher than the vehicle's advertised price.
How a Monthly Payment Becomes a Vehicle Budget
The tool works through a sequence rather than simply multiplying your monthly payment by the number of months.
Estimate APR
An estimated financing rate is selected based on the credit score, new or used vehicle choice, and current rate assumptions.
Estimate Loan Capacity
The payment, APR and loan term are used to estimate how much principal that monthly payment could support.
Add Upfront Value
Down payment and trade-in value are added to the estimated financing capacity.
Estimate Vehicle Range
Taxes and fees are considered and the result becomes an estimated vehicle purchase range.
Example of the Calculation
The numbers below are only an illustration of how the system works. They are not current loan offers or guaranteed rates.
Example Inputs
Example Output
After applying an estimated APR and transaction-cost assumptions, WhatCarFits would calculate a vehicle price range rather than present one artificially exact purchase price.
How We Estimate APR
The interest rate used in the calculator is an estimate designed to model affordability. It is not a personalized lender quote.
Rate Assumptions Can Consider
- Entered credit score
- New versus used vehicle
- Loan term
- Published auto-financing benchmarks
- Periodic updates to our internal rate table
Credit Score Is Not the Whole Loan Decision
A credit score can help estimate a likely borrowing-cost range, but lenders may also consider income, debt, loan-to-value, vehicle age, loan amount, term and other underwriting factors.
WhatCarFits Does Not Determine Approval
A result from WhatCarFits does not mean a lender will approve the loan, approve the same amount, or offer the APR used in the estimate.
How Down Payment and Trade-In Are Applied
These amounts can reduce the portion of the transaction that needs to be financed, but the site does not assume that more down payment is always the right choice for every person.
Down Payment
Added to the estimated financing capacity when determining the approximate purchase range.
Trade-In
Entered trade-in value is treated as available transaction value. An actual dealer offer may differ.
Net Amount Financed
Vehicle price, estimated taxes and fees, down payment and trade-in all influence the resulting financed amount.
Taxes and Fees
A vehicle's advertised price is not always the same as the final amount financed. Taxes and transaction costs can increase the total.
New and Used Vehicles Are Not Treated the Same
Financing rates, vehicle pricing and available terms may differ between new and used vehicles. WhatCarFits should account for those differences rather than using one universal rate assumption.
New Vehicles
New-vehicle financing may have different rates, incentives and loan structures than used-vehicle financing.
Used Vehicles
Used-vehicle financing can vary based on age, mileage, vehicle value and lender rules in addition to the borrower's credit profile.
Why We Show a Range Instead of One Exact Number
Affordability depends on assumptions that can change. A range is usually more honest than pretending one exact vehicle price is guaranteed to fit.
Comfortable Range
Vehicles somewhat below the calculated maximum may leave more room inside the user's selected monthly target.
Target Range
Vehicles close to the calculated affordability level may align more closely with the payment the visitor entered.
Near the Limit
Vehicles slightly above the target can be identified clearly rather than silently mixed in with lower-cost matches.
How Vehicle Matches Are Ranked
WhatCarFits should rank vehicles around the user's stated needs rather than simply placing the most expensive or highest-paying listing first.
What a WhatCarFits Result Does Not Mean
A result is meant to help with planning and comparison. It should never be mistaken for an approval or guaranteed transaction.
How We Keep the Methodology Current
The affordability model should be reviewed as market conditions, financing benchmarks and data providers change.
Transparency Comes Before Monetization
If WhatCarFits earns money from a vehicle listing, financing provider or other partner, that relationship should not secretly determine what is presented as the best match.
The Affordability Result Comes First
Visitors should be able to see their estimated range and matching vehicles before being required to submit lead information.
Sponsored Relationships Stay Labeled
Paid placements, referral relationships and affiliate links should be disclosed clearly when they are introduced.
See What Fits Your Budget
Enter the monthly payment you want to stay around, along with your down payment, credit score and financing preferences.