Public Data Sources

    These are the government and industry sources behind the calculator and our ownership guides. Each entry states what we take from the source. We do not treat a national average as a quote: your purchase contract, lender disclosure, insurer quote, utility bill, and state fee schedule should replace defaults whenever they are available.

    How the calculator uses public data

    Public datasets provide a defensible starting point, not a promise of what a particular car will cost. The calculator combines those references with user-entered purchase price, down payment, trade-in, APR, annual mileage, insurance premium, maintenance budget, and expected resale value. The formulas are documented separately so every total can be reproduced and challenged.

    See every formula in the methodology →

    Fuel, electricity, and vehicle efficiency

    These sources supply the price and efficiency inputs used to estimate gasoline or charging cost. We use the rating for the exact model whenever one is available; regional or state prices are starting points that users can replace with a local utility rate or pump price.

    Taxes, registration, and incentives

    Vehicle sales tax, title fees, registration charges, and incentive eligibility depend on location and transaction details. The calculator's location defaults are estimates, so the linked state agency and current IRS rules remain the authoritative sources before purchase.

    Financing and buyer protections

    Loan calculations use the amount financed, APR, and term entered by the user. These federal consumer resources explain required disclosures, optional add-ons, dealer practices, and used-car documentation rather than supplying a promotional rate.

    Insurance, safety, and price trends

    Insurance premiums are too personal and location-specific for a single public average to predict a driver's bill. We therefore recommend a vehicle-specific quote and use the insurance sources below for coverage definitions. Recall, safety, and price-index sources provide additional research context.

    Corrections and update policy

    Agencies revise tables, eligibility rules, and fee schedules on different calendars. We review links and assumptions when a guide changes, but readers should verify time-sensitive numbers at the linked source. If a source has moved or a calculator default no longer reflects its cited table, please send us the source and date.