How To Use Face ID On Your iPhone

Learn how facial recognition works with Apple devices

Face ID on iPhone
image credit: Apple Inc.

Face ID is a facial recognition system that replaces Apple's Touch ID fingerprint scanner on some devices. It uses sensors arrayed around the iPhone's user-facing camera to scan your face and, if the scan matches the data on file, perform actions like unlocking the phone or authorizing Apple Pay transaction.

What Is Face ID Used For on iPhone?

Face ID is used for many of the same things as Touch ID. Most important among these are:

  • Unlocking the iPhone in place of entering a passcode.
  • Supplying your Apple ID password or other passcodes.
  • Authorizing Apple Pay transactions. 

What Devices Support Face ID?

Face ID is supported by the full iPhone X series: the iPhone X, iPhone XS and XS Max, and iPhone XR.

It's a safe bet that, just like Touch ID started on the iPhone and has been added to other devices like the iPad, Face ID will eventually appear on other Apple devices such as the iPad.

How Does Face ID Work?

The notch at the top of the iPhone screen on compatible devices is where the sensors used by Face ID are located. These sensors include:

  • Dot Projector: This projects over 30,000 invisible dots onto your face. The dots are used to map the structure and depth of your face. That builds a three-dimensional "unique facial map," according to Apple.
  • Infrared Camera: This camera reads the dots from the Projector and captures an image. 
  • Flood Illuminator: This additional infrared light helps ensure that the system works even in the dark.

The facial map captured by the infrared camera is matched against the data stored on your iPhone to unlock or authorize the Apple Pay transaction. It's also used to create animoji, animated emojis mapped to your face.

The system is smart and sensitive enough, according to Apple, that it can recognize you even if you change your haircut, wear glasses, grow or shave a beard, and age. That said, there have been some cases in which Face ID has misidentified people, including twins and children who look a lot like their parents.

Is My Face Scan Stored in the Cloud?

No, Face ID face scans are not stored in the cloud. All face scans are stored directly on your iPhone. They are held in the "Secure Enclave," one of the iPhone's chips that's dedicated specifically to securing sensitive data. This is also where fingerprint information created by Touch ID is stored.

How Secure Is My Face Scan?

The way that the Secure Enclave works makes Face ID very secure. Your facial scan itself isn't actually stored on your iPhone. Instead, when the facial scan is created, it's converted to a number that represents the scan. That's stored in your iPhone.

Even if a hacker were able to access the data in your iPhone's Secure Enclave (which is very unlikely), all they would get is a number, not an actual scan of your face. That means they would not be able to use the data to submit your information to another facial recognition system.

How Does Face ID Compare to Other Smartphone Facial Recognition Systems?

Despite a health dose of skepticism when it was announced, Face ID has been a hit with users and critics. The overall consensus is that it's very accurate, very fast, and very simple. Overall, the transition away from Touch ID to Face ID has been faster and smoother than most people expected.

It's also proved, once again, how good Apple is at this sort of innovation. When Face ID launched there was one major phone out with this kind of technology: Samsung S8. Unfortunately, that system has been shown to be very easy to fool, including by holding up a photograph. Because of this, the Samsung system appears to not be terribly secure. Samsung won't allow its facial scans to approve financial transactions (the way Touch ID can on an iPhone).

How to Set Up and Use Face ID

Setting up Face ID is extremely simple — in fact, you probably did it while setting up your new iPhone. Just position your face in the onscreen frame and roll your head around until the circle around the edge of the frame is filled in. Repeat as many times as the phone tells you and you're done.

If you skipped that step during set up, you can always go back and add Face ID later. To do this, go to Settings > Face ID & Passcode and follow the onscreen instructions.

For some cool tips on using Face ID, check out The Best 8 iPhone X Face ID Hidden Features.

How to Disable Face ID

If you need to quickly disable Face ID, press the iPhone's side button and volume down buttons at the same time. In order to enable Face ID again, you'll need to re-enter your passcode.