How to Use the iPhone’s Compass and Level

Hang a painting or find your way home with your iOS device

What to Know

  • The Compass app is located on the iPhone Home screen.
  • You must calibrate the compass before first use. This is done by rotating the phone 360 degrees.
  • To measure the level in iOS 12, open the Measure app, then tap Level. In iOS 11, use the Compass app.

This article explains how to use the iPhone compass and level. Instructions apply to iPhones running iOS 12 and iOS 11 except as noted.

How to Use Your iPhone's Built-In Compass

To access the compass, open the Compass app, which appears by default on all current iPhone models. The application is located on the iPhone Home screen, but if you deleted it, reinstall it from the App Store for no charge.

Calibrate the Compass

When the app opens for the first time, you are prompted to calibrate the compass by rotating the phone 360 degrees. To aid the calibration process, follow the onscreen animation. After the device is calibrated, the compass screen displays.

Understand the Compass

Hold the iPhone parallel to the ground with the screen facing up. At the center of the compass is a small circle with a crosshair in the center. To ensure the phone is parallel to the ground, tilt the phone to align the crosshair with the center of the compass.

A small red arrow, situated above the letter N, points north. A long, bold white line at the top of the screen notes the current direction that the iPhone is facing.

iPhone screens showing how to select and use the Compass app

Compass directions are typically expressed in degrees. Infer your course by either seeing what number the white line at the top of the screen aligns with on the outside of the compass circle or by referencing the number at the bottom of the screen. The current degree the iPhone is facing updates as you rotate the device. The app also showcases letters indicating the four cardinal directions.

Compass Tips and Tricks

To keep a close eye on the way you are headed, face your destination and tap the center of the compass to establish a line of travel. As the compass moves away from that line, a red arc spreads between your intended heading and your current course. Adjust your path to return to the chosen course. To dismiss the arc, tap the center of the compass once more.

Depending on your location, you may also see additional information noting your GPS position in longitude and latitude, current geographical location, and your elevation above sea level. This information is not available in all areas.

How to Use the iPhone's Built-In Level

If you plan to hang a shelf or painting, use the Compass app's level function (in iOS 11 and earlier) to ensure that what you are hanging isn't tilted. In iOS 12, Apple split the measure function into a separate app, named Measure, but the functionality remained unchanged. To use it, open the Measure app, then tap Level.

Calibrate the Level

Calibrate the app with a point that is flush. The digital level indicates how far off the item is from being perfectly aligned with the original surface. For example, if you are hanging a painting on the wall and want it level with the floor, place the iPhone flat against the wall. This tells the device you are working on a vertical axis. Then, move the iPhone either to the top or bottom of the wall so that the edge of the device touches the ceiling or floor line (both the floor and ceiling are considered to be level).

Man and woman hang up a painting on the wall.
Chris Ryan / Getty Images

You'll see an indication of how far off level the phone is. Adjust the phone's position until the device is in a level position, then tap the screen. The level turns green and displays the number 0. Your iPhone's level function is now calibrated. Recalibrate the level each time you switch axes or align something differently.

The vertical Measure app calibration screens

Position an Object

Place the calibrated iPhone against an object such as a picture you are hanging on a wall. Rotate the object left or right while keeping the iPhone pressed against it. The number on the iPhone screen changes depending on how far out of level alignment the object is in relation to your initial calibration.

Adjust the object and the iPhone until the number 0 displays on the screen which indicates it is level. If you see other numbers, those numbers, expressed in degrees, indicate how far the object is from level. Continue to rotate the object and phone in the appropriate direction to bring the number back to zero.

Measure App Tips and Tricks

At any time in the leveling process, tap the screen to recalibrate the device if needed. When you measure in the vertical axis, the screen presents two small lines on the left and right sides of the screen. When you measure in the horizontal axis such as on a flat shelf, the screen shows two circles instead.

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