openpilot is an open-source, semi-automated driving software by comma.ai, Inc. When paired with comma hardware, it replaces advanced driver-assistance systems in various cars, improving over the original system. As of 2025, openpilot supports 325+ car models and has 10 000+ users, accumulating over 100 million miles (160,000,000 km). openpilot runs on comma 2/3/3X hardware, also developed by comma.ai. Packaged as an aftermarket retrofit, it allows users to enhance their existing cars with upgraded computing power, enhanced vision, and regularly updated software. openpilot has been cited to offer a "natural" and human-like driving experience, and reviewed favorably for its ease of use and driver engagement. As of May 2024, openpilot holds the record for the shortest time in a semi-autonomous, coast-to-coast drive across the U.S.
History comma.ai Inc was founded in September 2015 by George Hotz. The first version of openpilot was revealed a few months later in a Bloomberg article, showing functionality on a 2016 Acura ILX. The video and article instigated a cease and desist letter from the California Department of Motor Vehicles, claiming comma.ai was testing a self-driving car without a license. openpilot was packaged into a small, shippable device called the "comma one", announced at TechCrunch Disrupt. On October 27, 2016, NHTSA issued a Special Order to comma.ai demanding detailed information about the comma one, to determine if the device complies with legally required Federal Motor Vehicle Safety Standards. comma.ai responded in a tweet from Shenzhen, China, announcing the cancellation of the comma one. comma.ai open-sourced openpilot a month later, on November 30, 2016, emphasizing its intended use for research, without any warranty. On January 7, 2020, comma.ai introduced the $999 "comma two" device at CES in Las Vegas. In November 2020, Consumer Reports ranked openpilot above all other advanced driver-assistance systems on the market, including Tesla's Autopilot, Cadillac's Super Cruise and Ford's Co-pilot 360. In particular, openpilot's performance in the areas of driver engagement and ease of use scored better than all other systems evaluated by Consumer Reports.
At comma's 2021 comma_con convention, the company released the "comma three devkit". This model uses two fish eye cameras oriented to the front and a long distance camera oriented to the rear to analyze the car's surroundings. In January 2023, The Verge found openpilot-based driving-assist technology to be better than that from legacy car manufacturers, delivering more "natural" and human-like driving experience. Nearly 5000 units of openpilot-supported Comma 3 devices were already said to be distributed. At comma's 2023 COMMA_CON convention, the "comma 3X" was announced as a successor to the comma three devkit at a lower price of $1249. In 2023, the total distance driven by openpilot's 6000+ users was said to have exceeded 90 million miles, an improvement over the 25 million miles figure reported in 2020. In April 2024, a new semi-autonomous Cannonball run record, involving a drive across the United States from the East Coast to the West Coast, was set using a 2017 Toyota Prius equipped with a comma 3X unit running openpilot. The drive took 43 hours and 18 minutes at 98.4% autonomy, (an average of 67 miles per hour (108 km/h)), beating the previous record set in a Tesla Model S (97.7% autonomy) by nearly 12 hours.
Comma Hardware
Features
In contrast to traditional autonomous driving solutions where the perception, prediction, and planning units are separate "modules", openpilot adopts a system-level end-to-end design to predict the car's trajectory directly from the camera images. openpilot's end-to-end design is a neural network that is trained by comma.ai using real-world driving data uploaded by openpilot users.
Navigate on openpilot openpilot 0.9.4 and onwards include "navigate on openpilot", a feature akin to "Full Self-Driving" (FSD) from Tesla, Inc.
Automated lane-centering openpilot uses machine learning, trained with real-world driving data, to determine the safest path on the road. This improves perception on roads without lane markings vs. lane-centering by tracking current lane lines.
Adaptive cruise control openpilot maintains a safe following distance from the vehicle ahead. It is capable of driving in stop-and-go traffic with no user intervention. It uses OpenStreetMap's road curvature and speed limit data to allow slowing on sharp turns and setting the vehicle's desired speed to the current speed limit on certain community-maintained forks of the main repository.
Driver monitoring openpilot recognizes the driver's face; if the driver is distracted, openpilot warns the driver. If the driver is distracted for more than six seconds, openpilot decelerates the vehicle to a stop, and audibly alerts the user.
Assisted lane change openpilot uses the model to change lanes when the user engages the turn signal: a nudge is optional on the steering wheel to confirm the lane change. openpilot also interacts with the blind spot monitor on certain makes and models to block the lane change in the event a car is detected by the blind spot monitor.
Software updates openpilot receives over-the-air software updates via WiFi or a cellular phone network, (OTA updates).
Supported cars At launch, openpilot supported the Honda Civic and the Acura ILX. Support for more vehicles and brands has been added through open-source contribution. As of March 2026, the list of officially supported vehicles contains more than 325 entries, and can be viewed at https://comma.ai/vehicles. The latest complete list, including community supported cars, can be found at https://github.com/commaai/opendbc/blob/master/docs/CARS.md.
Community Development is supported by an open-source community using Discord and GitHub. comma.ai has released tools and guides to help developers port their cars. In addition, they released tools to let users review their drives.
Forks comma.ai maintains the openpilot codebase and releases, and there is a growing community that maintains various forks of openpilot. These forks consist of experimental features such as stop light detection. Pre-Autopilot Tesla models have been retrofitted with openpilot through a community fork. Chrysler and Jeep models have also gained support through community contributions. There are over 6,600 forks of the openpilot GitHub repository.
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