# Level Horizon Calibration

You can use *Level Horizon Calibration* to compensate for small misalignments in controller orientation and to level the horizon in the *QGroundControl* flight view (blue on top and green on bottom).

:::tip Leveling the horizon is highly recommended, and will result in the best flight performance. This process can also be repeated if you notice a constant drift during flight. :::

## Performing the Calibration

To level the horizon:

1. Start *QGroundControl* and connect the vehicle.
2. Select the **Gear** icon (Vehicle Setup) in the top toolbar and then **Sensors** in the sidebar.
3. Click the **Level Horizon** button. ![Level Horizon calibration](/files/afwbPmzvzODQHjvkvOwA) :::note You should already have set the [Autopilot Orientation](/px4-user-guide/config/flight_controller_orientation.md). If not, you can also set it here. :::
4. Place the vehicle in its level flight orientation on a level surface:

* For planes this is the position during level flight (planes tend to have their wings slightly pitched up!)
* For copters this is the hover position.

1. Press **OK** to start the calibration process.
2. Wait until the calibration process is finished.

## Verification

After the orientation is set and level-horizon calibration is complete, check in the flight view that the heading in the compass shows a value around 0 when you point the vehicle towards north and that the horizon is level (blue on top and green on bottom).

## Further Information

* [Advanced Orientation Tuning](/px4-user-guide/advanced_config/advanced_flight_controller_orientation_leveling.md) (advanced users only).
* [QGroundControl User Guide > Sensors](https://docs.qgroundcontrol.com/master/en/SetupView/sensors_px4.html#level-horizon)
* [PX4 Setup Video "Gyroscope" - @1m14s](https://youtu.be/91VGmdSlbo4?t=1m14s) (Youtube)


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