While both accessories can make a vehicle more aerodynamic, a wing tends to be more effective than a spoiler in generating downforce at very high speeds. At normal, road-going speeds, however, a wing is unlikely to improve vehicle performance. That's why most production vehicles have spoilers, rather than wings.

The reason that wings are used on professional race cars and other high-performance vehicles is that they need the additional downforce. A rear wing will essentially catch the air coming off of the car and redirect it up so that the back of the car is pushed down.

Spoilers are designed to increase a vehicle's aerodynamics and reduce overall drag.

The goal of many spoilers used in passenger vehicles is to reduce drag and increase fuel efficiency. Passenger vehicles can be equipped with front and rear spoilers. Front spoilers, found beneath the bumper, are mainly used to decrease the air going underneath the vehicle to reduce the drag coefficient and lift.