Understanding NHTSA 5-Star Safety Ratings

NHTSA's 5-Star Safety Ratings come from the federal New Car Assessment Program (NCAP), which has been crash-testing new vehicles since 1979. The stars are a quick way to compare how well vehicles protect occupants in certain kinds of crashes and how likely they are to roll over. Used well, they help you choose between models. Used carelessly, they can mislead you, because the stars do not all mean the same thing across vehicle sizes or model years.

This guide explains each rating, the rules for comparing them, what they leave out, and how they fit alongside other sources.

Test details come from NHTSA's program descriptions on nhtsa.gov/ratings (opens in a new tab), where you can also look up any rated vehicle.

In the frontal test, the full width of the vehicle's front hits a rigid barrier at 35 mph, roughly like two vehicles of the same weight hitting head-on at that speed. Dummies in the driver and front passenger seats record forces on the head, neck, chest and legs. NHTSA converts those readings into an injury risk and then into stars, with separate stars for driver and passenger.

Side impacts are especially dangerous because there is little structure between the occupant and the striking object.

• Side barrier test. A barrier on a moving cart, representing a midsize vehicle, strikes the driver's side at 38.5 mph. Dummies in the front and rear seats measure injury risk.
• Side pole test. The vehicle is pushed sideways into a narrow pole at 20 mph, at an angle, at the driver's position. It tests head protection from side curtain airbags and structure against a concentrated hit.

The side rating combines these. Side ratings are generally more comparable across vehicle sizes than frontal ratings, because the barrier represents the same striking vehicle every time.

The rollover rating estimates the chance a vehicle rolls over in a single-vehicle crash where the driver loses control. It is based on:

• Static stability factor, a calculation from the vehicle's track width and center of gravity height. Taller, narrower vehicles score lower.
• A dynamic test, in which the vehicle performs a sharp steering maneuver to see whether it tips up.

The result is shown as stars and as a percentage risk of rollover. Unlike the crash ratings, it does not measure how well the vehicle protects you if it rolls. Wearing a seat belt has a large effect on survival in a rollover; NHTSA's site covers rollover safety in more detail.

The overall score combines the frontal, side and rollover results into a single number of stars. It is useful for a quick comparison, but look at the individual ratings too. A vehicle can earn a good overall score while having a weaker result in one area, such as the passenger's frontal rating or rollover risk.

Alongside stars, NHTSA's ratings pages show whether a vehicle has certain recommended driver-assistance technologies, such as forward collision warning, lane departure warning, automatic emergency braking and others. The list has been updated over time, and NHTSA has announced program updates that expand the technologies it evaluates. Check nhtsa.gov/ratings (opens in a new tab) for the current criteria for the model year you are looking at.

Keep in mind that a feature listed as "optional" is only on the car if that trim or package was ordered. On a used car, confirm it is actually fitted.

Compare the same model year

NHTSA updated its testing and rating methods starting with the 2011 model year, adding the side pole test and changing how results are scored. Stars from before that change are not directly comparable to newer ones. Ratings also apply to a specific model year and body style. After a redesign, the old ratings no longer apply.

Check the exact version

Ratings can differ between two-wheel drive and all-wheel drive versions, between body styles (sedan vs hatchback, regular cab vs crew cab), and sometimes between trims. Use the VIN decoder to confirm a car's exact configuration, then match it on NHTSA's site.

"Not rated" does not mean unsafe

NHTSA does not test every model every year. Low-volume vehicles, some heavy-duty pickups and many specialty vehicles are not rated. A missing rating means no NHTSA test result, not a bad one.

Stars measure occupant protection, not crash avoidance

The crash ratings show what happens once a crash occurs. Brakes, handling, visibility, headlights and driver-assistance features affect whether you crash in the first place. Some of that is partly captured in the technology list, but not in the stars.

The Insurance Institute for Highway Safety (IIHS) is a separate organization funded by insurers. Its ratings are a useful complement, not a substitute.

The two programs test different crash types, so a vehicle can do well in one and less well in the other. Looking at both gives you a more complete picture.

Safety ratings are one piece of a model year's record. Before buying, also check:

• Recalls for that model year, especially open ones on the specific car. See our guide to checking recalls by VIN.
• Owner complaints by component. Our research pages, such as /cars/toyota/rav4/2019, show NHTSA safety ratings alongside recalls and complaints for that year.
• The specific car's condition, through a careful inspection. Our used car inspection checklist covers what to look for.

Prior crash damage, poor repairs and worn tires or brakes can make any vehicle less safe than its ratings suggest.