Face ID is Apple’s flagship biometric security system. By using a complex array of infrared cameras and dot projectors hidden in the “notch” (or Dynamic Island) at the top of your screen, your iPhone can create a flawless 3D mathematical map of your face.
This allows you to unlock your device, authenticate Apple Pay purchases, and log into your banking apps simply by looking at the screen, entirely bypassing the need to type out a tedious passcode dozens of times a day.
How to Set Up Face ID
You are normally prompted to set up Face ID when you first turn on a brand new iPhone. However, if you skipped that step, or if you recently reset your phone, you can configure it manually in the Settings app.
- Open the Settings app on your iPhone.
- Scroll down and tap on Face ID & Passcode.
- Enter your 6-digit numerical passcode to gain access to this highly secure menu.
- Tap the blue text that says Set Up Face ID.
- Hold your iPhone directly in front of your face in portrait orientation (vertically), about 10 to 20 inches away.
- Tap Get Started.
The screen will display a circular frame. You must position your face so it fits entirely inside this circle.
- Slowly and smoothly roll your head in a circle to complete the green progress bar on the screen. Imagine you are using your nose to draw the outer edge of a circle.
- Once the first scan is complete, tap Continue.
- You will be asked to perform the exact same slow head roll a second time to ensure the 3D map is completely accurate.
- When the second scan finishes, tap Done.
Face ID is now fully active. The next time your phone is locked, simply swipe up from the bottom of the screen while looking at the device, and it will instantly unlock.
Setting Up an Alternate Appearance
Face ID is designed to automatically adapt to minor daily changes, such as wearing different glasses, growing a beard, or wearing a hat. However, if you have a job where you must wear heavy safety goggles or a thick medical mask, the system may struggle to recognise you.
To fix this, you can train the iPhone to recognise a completely different version of your face.
- Navigate back to Settings > Face ID & Passcode.
- Tap on Set Up an Alternative Appearance (or “Face ID with a Mask” on newer iOS versions).
- Follow the exact same head-rolling scanning process as before, this time wearing your mask or heavy glasses.
A Note on Security
Face ID is incredibly secure. The infrared 3D map means it cannot be fooled by a photograph or a video of your face, and it requires “attention” by default—meaning your eyes must be physically open and looking at the screen for the phone to unlock. It will not unlock if you are asleep.