Federal Fuel Economy Guide

The purpose of EPA’s fuel economy estimates is to provide a reliable basis for comparing vehicles.

A “city” estimate that represents urban driving, in which a vehicle is started in the morning (after being parked all night) and driven in stop-and-go traffic
A “highway” estimate that represents a mixture of rural and interstate highway driving in a warmed-up vehicle, typical of longer trips in free-flowing traffic
A “combined” estimate that represents a combination of city driving (55%) and highway driving (45%)

Estimates for all vehicles are based on laboratory testing under standardized conditions to allow for fair comparisons.