Car Depreciation Calculator

Vehicle depreciation is modelled here as declining balance rather than straight line, because a car loses a percentage of its remaining value each year rather than a fixed dollar amount. The first year is treated separately at an elevated rate, since the largest single loss occurs when a titled vehicle moves from new to used inventory and can no longer be sold at manufacturer pricing. Typical parameters: a first-year drop of 20 to 30 percent for mainstream models and 30 to 40 percent for luxury marques, followed by 12 to 18 percent of remaining value annually. Compounding at those rates leaves roughly 40 to 50 percent of sticker price after five years, which matches the widely quoted rule that a new car retains about half its value over that span. Mileage enters as an adjustment against an assumed norm of about 12,000 to 15,000 miles per year in the United States, since valuation guides price a vehicle against expected accumulated mileage for its age rather than against odometer reading alone. Depreciation is normally the single largest ownership cost, exceeding fuel and insurance combined in early years; AAA's annual Your Driving Costs study has consistently found depreciation to be the dominant line item for new vehicles. The model has real limits. It cannot capture model-specific residual strength, so a Toyota Tacoma or Jeep Wrangler will beat any generic rate while a discontinued luxury sedan will fall below it. It also assumes a stable market, which failed conspicuously in 2021 and 2022 when semiconductor shortages pushed some used values above their original purchase price.

Formal depreciation accounting for vehicles predates any consumer resale guide. The US Internal Revenue Service permitted depreciation deductions on business property from the early income tax era, and the Accelerated Cost Recovery System introduced by the Economic Recovery Tax Act of 1981, later modified into the Modified Accelerated Cost Recovery System in 1986, fixed automobiles in a five-year recovery class using a 200 percent declining balance method. That declining balance mathematics is the same structure used here, though tax schedules describe allowable deductions rather than market value. Market-based valuation grew from the used car trade itself. Les Kelley, a Los Angeles car dealer, began circulating lists of vehicles he wanted to buy in 1918; the resulting Kelley Blue Book was first published as a dealer reference in 1926 and became the standard wholesale and retail price guide. The National Automobile Dealers Association launched its own Official Used Car Guide in 1933. Both were dealer tools for decades before consumer access. The Automotive Lease Guide, founded in 1964, developed the residual value forecasting that underpins lease pricing, since a lease payment is essentially the predicted depreciation over the term plus finance charges. Consumer-facing depreciation data became widely available only with the arrival of Edmunds and Kelley Blue Book online in the mid-1990s, which is when buyers could first check resale projections before signing.