On the iPhone 12 Pro, iPhone 12 Pro Max, iPhone 13 Pro, and iPhone 13 Pro Max, you can use the Measure app to instantly measure a person’s height from the floor to the top of their head, hair, or hat.
You can even measure the seated height of a person in a chair. Here’s how:
- Position the iPhone so that the person you want to measure appears on the screen from head to toe. After a moment, a line appears at the top of the person’s head (or hair, or hat), with the height measurement showing just below the line.
- To take a photo of the measurement, tap the shutter icon.
- To save the photo, tap the screenshot in the lower-left corner, tap Done, then choose Save to Photos or Save to Files. You can access and share the height measurement image from Photos or Files on iPhone whenever you want.
To take the measurement again, turn iPhone away for a moment to reset the height.
(This how-to is based on my experiences and info on Apple’s support pages.)