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Data sources
Vehicle fuel economy is based on the EPA and U.S. Department of Energy FuelEconomy.gov vehicle dataset, model years 1984–2027. The local file includes gasoline and diesel vehicle configurations; identical displayed configurations are combined. Ratings can be revised, including 2027 model-year entries. For plug-in hybrids, the displayed MPG is for gasoline operation and does not include electric driving. The default 28 MPG is an editable assumption, not a rating for a particular car.
Fuel prices are based on published retail averages and are saved locally with their observation dates. City or area prices represent local averages, not individual stations. If a local price is unavailable, the calculator uses the state average or the national average. You can always enter your own price. The national average comes from the U.S. Energy Information Administration’s weekly retail survey.
Enter the distance and any known tolls manually. Prices and estimates can differ from actual charges.