The comma four is the primary supported device for running openpilot in a car. It is designed specifically for this purpose — plug it into a compatible car harness, mount it on your windshield, and openpilot is ready to drive. No configuration or compilation required.Documentation Index
Fetch the complete documentation index at: https://mintlify.com/commaai/openpilot/llms.txt
Use this file to discover all available pages before exploring further.
comma four
The only officially supported device for running openpilot in a vehicle
Car harness
Vehicle-specific harness that connects the comma four to your car’s ADAS system
comma four
The comma four is available at comma.ai/shop/comma-four. It is purpose-built hardware for running openpilot, with onboard cameras, GPS, IMU, and LTE connectivity. The device mounts to your windshield and draws power through the car harness. The comma four runs therelease-mici branch by default when installed via openpilot.comma.ai. It is the recommended device for all openpilot users.
Car harness
The car harness connects the comma four to your vehicle’s existing ADAS connector. It intercepts the CAN bus and camera signals that openpilot needs to control steering, acceleration, and braking through the car’s stock systems. Order the harness that matches your specific car make, model, and year from comma.ai/shop/car-harness. Using the wrong harness for your vehicle is not supported and may not work. The harness does not require permanent modifications to the vehicle. It plugs in and out cleanly.Branches and device compatibility
openpilot ships prebuilt branches for each supported device. Use the branch URL that matches your device during the setup flow.| comma four branch | comma 3X branch | URL | Description |
|---|---|---|---|
release-mici | release-tizi | openpilot.comma.ai | Stable release branch — recommended for daily driving |
release-mici-staging | release-tizi-staging | openpilot-test.comma.ai | Staging branch — new releases arrive here first |
nightly | nightly | openpilot-nightly.comma.ai | Bleeding edge — may be unstable |
nightly-dev | nightly-dev | installer.comma.ai/commaai/nightly-dev | Nightly plus experimental car features |
release-mici vs release-tizi) but share the same nightly and nightly-dev branches. Running master or other source branches directly is also supported for development purposes.
Running on other hardware
It is possible to run openpilot on hardware other than the comma four. comma has published a guide on running openpilot for free on alternative hardware. For development and simulation work on a desktop, openpilot is developed and tested on Ubuntu 24.04. Most of openpilot also works natively on macOS. See the development environment guide for setup instructions.Next steps
Quickstart
Step-by-step guide to installing openpilot and taking your first drive
Supported cars
Check whether your vehicle is one of the 300+ supported cars