When the NHTSA completes a test on a vehicle, they will share their rating on a scale of one to five stars. They will give a vehicle a certain number of stars based on how well they think it did on the test. The higher the number of stars from the NHTSA, the safer the vehicle.
When the IIHS completes a test on a vehicle, they have a somewhat simpler rating system that they use. They will rate a vehicle anywhere from "poor" to "good" depending on how the vehicle did in a test. Their other rating options are "marginal" and "acceptable".
