When someone asks if a car “gets good gas mileage,” one logical response is: Compared to what? What qualifies as “good” is a relative term. The fairest way to judge whether a vehicle gets good mileage is to see how it stacks up against similar vehicles; compare a compact sedan to other cars like it or a V-8 pickup truck to other pickups. Comparing vehicles of a similar size and weight and with similar engines isn’t likely to reveal huge differences because manufacturers target their key competitors in areas such as fuel economy.