Imagine standing in a furniture store looking at a beautiful new sofa. You know roughly how large your living room is, but you do not know if this specific sofa will fit through your front door. Unfortunately, you left your metal tape measure sitting in your toolbox at home.
You actually have a highly accurate tape measure in your pocket right now. Apple pre-installs an application called “Measure” on every modern iPhone. Using advanced Augmented Reality (AR) algorithms and the camera array on the back of your phone, this app can calculate the physical dimensions of real-world objects with astonishing accuracy.
This guide explains how to use the hidden Measure app on your iPhone to quickly measure objects and spaces.
Step 1: Open the Measure App and Calibrate
The Measure app is installed by default on all iPhones running modern versions of iOS, but it is often buried inside a folder on the second or third page of the Home Screen.
- Swipe down from the middle of your Home Screen to open the Spotlight Search bar.
- Type the word Measure.
- Tap the Measure app icon (it looks like a black icon with a yellow ruler).
- When the app opens, the camera will activate. The app will usually display a message asking you to “Move your iPhone to start.” Slowly pan your camera around the room, focusing on flat surfaces like tables or the floor. This allows the iPhone’s sensors to map the 3D space around you.
Step 2: Take a Manual Measurement
Once the app is calibrated, a white circle with a dot in the center will appear on your screen. This dot acts as your virtual tape measure.
- Point your camera so the white dot rests exactly on the starting edge of the object you want to measure (e.g., the left armrest of the sofa).
- Tap the large “+” (Plus) button at the bottom of the screen to lock in the starting point.
- Slowly pan your iPhone across the object until the white dot reaches the ending edge (e.g., the right armrest). As you move the phone, a yellow dotted line will extend across the screen, displaying the distance in real-time.
- When you reach the end, tap the “+” (Plus) button again to lock in the endpoint.
- The exact measurement will be displayed in bold white text floating above the object.
Step 3: Advanced Tips and Tricks
The Measure app has a few brilliant hidden features to make measuring even easier:
- Automatic Rectangle Detection: If you point the camera at a perfectly rectangular object, like a framed painting or a television screen, the app will automatically detect its edges and highlight it with a yellow box. Simply tap the “+” button, and the app will instantly calculate both the length and the width simultaneously without requiring you to trace the edges manually.
- Take a Photo of the Measurement: Once you have placed your measurement lines, tap the white shutter button in the bottom right corner of the screen. The iPhone will take a photograph of the object with the yellow measurement lines permanently overlaid on top of it, allowing you to reference the dimensions later.
- Check if a Surface is Level: Tap the Level tab at the very bottom of the screen. You can now place your iPhone flat on a table or hold its edge against a picture frame to determine if the surface is perfectly flat. The screen will turn bright green when you hit 0 degrees.