If you need to quickly check how tall your child has grown, or verify the height of a friend without hunting for a physical tape measure, your iPhone can do the math for you almost instantly.
Modern iPhones (specifically the “Pro” and “Pro Max” models from the iPhone 12 onwards) are equipped with a LiDAR scanner. This is a highly advanced laser-radar system located in the camera bump that fires invisible pulses of light to map the physical world in 3D. Apple leverages this hardware to instantly and accurately measure human height.
How to Measure a Person’s Height
This feature works automatically within the built-in “Measure” app. You do not need to download any third-party software.
- Locate and open the Measure app on your iPhone. (It has a black icon with a yellow ruler on it. If you cannot find it, swipe down on your home screen and type “Measure” into the search bar).
- Ensure the room is well-lit. The LiDAR scanner works best when there is clear contrast.
- Ask the person you want to measure to stand straight against a flat wall, facing you. (They can be seated in a chair, and the iPhone will measure their seated height, but standing provides the most accurate full-body result).
- Hold your iPhone vertically and point the camera at the person.
- Step back until the person’s entire body (from their feet to the very top of their head) is visible within the iPhone screen.
The iPhone will recognize that there is a human in the frame and instantly draw a white line horizontally across the top of their head.
- The exact height measurement will automatically pop up in a white box resting on that line.
Does it Measure Hair and Hats?
The LiDAR scanner is incredibly sophisticated. It is designed to measure to the top of the person’s physical head, or the top of their hair—whichever is highest. If the person is wearing a tall top hat or a thick beanie, the iPhone will measure to the top of the hat, artificially inflating their height.
For the most accurate measurement, the subject should remove any headwear and flatten their hair as much as possible.
How to Save the Measurement
Because the measurement disappears as soon as the person walks out of the camera frame, you might want to save a record of it.
- While the height measurement is still hovering above the person’s head, look at the bottom right corner of the screen.
- Tap the white circular Shutter Button.
This will snap a photograph of the person with the height measurement permanently overlaid on top of them, and save it directly to your Camera Roll for future reference.