
The IIHS is a non-profit that is funded by car insurance companies. Each vehicle they rate undergoes five different collision tests to see how it reacts. Once the results are compiled, a car is given a Poor, Marginal, Acceptable, or Good rating. For cars that perform exceptionally well, a Top Safety Pick award is given.
The NHTSA uses two different collision tests for their rating system. They also use the car's center of gravity and width to determine its roll-over potential. A safety rating is given on a five-star scale.