openpilot

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.