Explaining The 6 Levels Of Automated Driving, And Which Ones Are Actually On U.S. Roads

If there’s one piece of automotive technology that really feels more like The Future than anything else, it’s the automated driving systems that have quickly proliferated across the industry. Commonly people might describe vehicles with such systems as being “self-driving” or “semi-autonomous” cars, but that’s not entirely accurate — especially not for Tesla’s so-called “Full Self-Driving” and “Autopilot” technology suites.

As (I’m assuming) Socrates once said, there’s levels to this. New cars have so many different types of active and passive safety systems, not all of which do things like accelerate, brake and steer to support the driver. And just because your car has an adaptive cruise control system that allows for hands-free driving does not mean you’re not in control of and responsible for your car. But then you’ve got companies like Waymo that are offering genuinely driverless rides to paying passengers.

To make things easy to understand for automakers, tech companies and consumers alike, the Society of Automotive Engineers (SAE) defined six levels of driving automation that go from Level 0, where there’s no automated driving systems at all, to Level 5, which is full driving automation — at that point, you can really call it a self-driving car. SAE first released these guidelines in 2021, but four years later things have changed so much in the automotive world that we thought it time to revisit the levels of automated driving and tell you what exactly is on U.S. roads, and what you can buy yourself.

Level 0, Level 1 and Level 2 are all considered “driver support” features, where Level 3, Level 4 and Level 5 are “automated driving” features. Some Level 1 and Level 2 tech can be considered “semi-automated,” but in those cases the driver is still in control, needing to be engaged and constantly supervising the vehicle at all times.

We start out at Level 0, where you’ve got no automated driving features at all. Common features like automated emergency braking, blind-spot monitoring and lane-departure warning all fall under this category, as they give the driver warnings or provide brief assistance. At Level 1 you’ve got adaptive cruise control systems that accelerate and brake for the driver, using things like radar and traffic info to automatically adjust speeds, or systems that provide some steering assist, like lane-centering.

Level 2 systems can provide steering assist and acceleration/braking assist at the same time, through features like lane-centering and lane-keeping assists that provide steering input to keep you in the lane when adaptive cruise control is on. At this point it’s pretty rare to find a new car that only meets the Level 1 criteria; the vast majority of new cars will fall under the Level 2 umbrella given how common it is for these active-safety systems to be standard (or at least optional), on everything from popular vehicles like the Toyota RAV4 and Ford F-150 to wild stuff like the Lamborghini Revuelto. With a Level 2 system on, you need to always be paying attention and have your hands on the steering wheel

There can be a big difference between Level 2 driver-assist systems, though, one that has prompted people to come up with a “Level 2.5” moniker. BMW’s Highway Assistant, Ford’s BlueCruise, General Motors’ Super Cruise, Stellantis’ Active Driving Assist, Nissan’s ProPilot Assist, and Toyota’s Teammate can all do hands-free driving. That means that instead of needing to keep a light touch on the steering wheel when you’ve got adaptive cruise control and lane-keeping assist turned on, you can take your hands off the wheel completely. These hands-free systems are typically only able to be activated on mapped freeways, with restrictions on things like speed and weather conditions, and the driver always must be immediately ready to take back control.

Then you’ve got Tesla. Both its “Autopilot” and “Full Self-Driving” systems are just Level 2 hands-free systems, where the driver must be in control at all times. The difference is, Tesla will let its owners use these systems on pretty much any type of road, with Autopilot requiring lane markings but FSD able to be activated anywhere. This misleading marketing has lead to downgraded safety scores and daily fines in some countries. Then there’s the issue of new Teslas going to a solely camera-based system, where every other automaker uses different sorts of sensors like lidar and radar, and with even more redundancies. Then there’s how unsafe Tesla’s systems are — there have been many instances of Teslas using “Autopilot” or “Full Self-Driving” crash into deer and police cars, kill pedestrians and motorcyclists, accelerate into railings, get hit by trains, and cause all sorts of other accidents. One test found that a driver had to take over every 13 miles.

Now it gets more interesting. At these levels, instead of just providing accelerating, braking and steering support to the driver, the vehicles can drive themselves without driver intervention being necessary — but there’s still some caveats. With a Level 3 system engaged the driver must be able to take back control if the system asks, but otherwise the vehicle is able to drive itself when specific conditions are met.

Currently there’s only one Level 3 system available to customers in the U.S., and it’s from Mercedes-Benz, not Tesla. The German brand’s Drive Pilot system is the first to be certified by the SAE and approved for sale in the U.S., currently available in California and Nevada on the EQS and S-Class. On approved freeways, in the daytime with clear weather, you can activate Drive Pilot to be able to take both your hands and eyes off the road. The system works at up to 40 mph, but Mercedes aims to increase the approved speeds — in Germany it can already go up to 60 mph. With this Level 3 system active, the driver is free to watch a movie or play a game on the center screen, read a book or write in a journal, more easily eat a sandwich, have a more comfortable conversation with other passengers, and even use your cellphone if the area you’re in doesn’t have laws agains that. I’ve tried Drive Pilot in horrible Los Angeles traffic, and it was truly revelatory. Honda offers a Level 3 system in Japan, and BMW sells one in Germany. Lots of other companies are working on Level 3 systems, too.

When a Level 3 system is active, the driver still needs to be prepared to take back control if necessary — that means you can’t take a nap or climb into the back seat. For example, if the Mercedes detects that it’s coming up on a construction zone, or if traffic starts moving faster than the allowed top speed, the car starts making chimes and turning the steering wheel lights red. If the driver doesn’t immediately react, the warnings will get louder and more frequent, and it’ll tug on your seatbelt and vibrate the seat and steering wheel. After 10 seconds, if the driver still hasn’t taken back control, the car will come to a stop, turn on the hazards and call emergency services.

Now we’re at the point where you could call one of these vehicles a “self-driving car” without me jumping in to “well, actually” you. Level 4 systems are only available under certain conditions, like with Level 3, but a driver will never be required to take over, and it’s not necessary to have one in the car at all. The most common Level 4 cars you’ll see in the U.S. are Waymos, and other driverless taxis are starting to emerge. Typically these sorts of vehicles are geofenced, where they’re only allowed to drive on certain roads or in certain areas — for example, Waymos in LA can’t go on the freeway yet, and they only recently started being able to tackle hilly neighborhoods. Level 4 cars also don’t require steering wheels or pedals, and Waymo’s upcoming Zeekr-based van won’t have them.

Finally you’ve got Level 5, which is where a vehicle can drive itself anywhere and everywhere under all conditions. There are currently no Level 5 vehicles of any sort, and there likely won’t be for a while. Level 4 covers basically all of those bases, and at this point with the technology and in our society it’s probably better to have things like geofencing and remote supervision if needed. It’ll also likely be quite a while until a Level 4 or Level 5 vehicle is actually able to purchase and be used by civilians, despite what Elon Musk says.

So, there you have it. Hopefully now you have a better understanding of the different levels of automation and what is actually running around on our roads, so next time an annoying guy at the bar starts talking to you about how his Tesla drives itself, you can shut him down.