Can someone unlock your phone while you sleep?

iPhoneAndroidUpdated

You woke up and the phone wasn't quite where you left it, or an app was open that you don't remember using. The short answer: Face ID is built to make this hard, fingerprints are not, and Android face unlock depends on your settings.

Quick answer

Apple says Face ID checks that your eyes are open, which makes it more difficult for someone to unlock your iPhone while you're sleeping, as long as Require Attention for Face ID is on. Fingerprint unlock checks the finger, not whether you're awake. Android face unlock varies: turn on Require attention on screen (Pixel) or Require open eyes (Samsung).

Can someone unlock my iPhone with Face ID while I'm asleep?

Apple says Face ID is attention-aware and recognises if your eyes are open, which makes it more difficult for someone to unlock your device without your knowledge, such as when you're sleeping. That protection depends on one accessibility setting staying on. Apple also says Face ID allows only five failed matches before it asks for the passcode.

  1. Go to Settings > Accessibility > Face ID & Attention.
  2. Check that Require Attention for Face ID is on. Apple notes it's turned off automatically if you turned on VoiceOver when you first set up the iPhone.
  3. In Settings > Face ID & Passcode, leave Attention Aware Features on unless you have a reason not to.

Can someone unlock my phone with my fingerprint while I'm asleep?

Fingerprint unlock checks the finger on the sensor. Neither Apple's Touch ID pages nor Google's fingerprint pages describe any check that you're awake. Google is direct about the limits: a fingerprint can be less secure than a strong PIN, pattern or password, and a copy of your fingerprint could be used to unlock your phone.

If that worries you, lock down the phone before you sleep (see below) so it needs your passcode or PIN, and check that only your own fingerprints are saved. Google says anyone whose fingerprint you add can unlock your phone.

Is Android face unlock safe while you sleep?

It depends on the settings. Google says Pixel Face Unlock can be unlocked by someone else if the phone is held up to your face, and may be less secure than a strong PIN, pattern or password. Samsung says face recognition is less secure than a pattern, PIN or fingerprint. Both offer a setting that helps.

On a Pixel (Pixel 7 or later):

  1. Open Settings and tap Security and privacy > Device unlock > Face.
  2. Enter your PIN, pattern or password.
  3. Under 'When using Face Unlock', turn on Require attention on screen. Google says you then must look directly at the screen to unlock.

On a Samsung Galaxy (menu names can vary by model):

  1. Open Settings and tap Security and privacy > Biometrics > Face recognition.
  2. Enter your PIN, pattern or password.
  3. Turn on Require open eyes. Samsung says the device will then only recognise your face when your eyes are open.

On a Pixel, also check Settings > Security and privacy > More security and privacy > Extend Unlock. Google says a trusted place can keep the phone unlocked within up to about 100 metres.

Could someone have added their face or fingerprint?

It's worth checking, because an extra face or fingerprint would let someone else in at any time. Apple's Personal Safety guide says that if you think someone added an alternative Face ID appearance without your permission, reset Face ID and set it up again. Adding a fingerprint to Touch ID needs your passcode, so whoever did it knew the code.

On iPhone with Face ID:

  1. Go to Settings > Face ID & Passcode and enter your passcode.
  2. Tap Reset Face ID. This removes your appearance and any alternate appearance.
  3. Tap Set up Face ID and scan only your own face.

On iPhone with Touch ID:

  1. Go to Settings > Touch ID & Passcode.
  2. Place a finger on the Home button to identify its print. Do this with each finger you use, and any print none of them identifies isn't yours.
  3. Tap that fingerprint, then tap Delete Fingerprint.

On a Pixel, go to Settings > Security and privacy > Device unlock > Fingerprint, and tap Delete next to any fingerprint you don't recognise. Google says you can add up to four. On Samsung, remove face data in Settings > Security and privacy > Biometrics > Face recognition.

If someone added a face or fingerprint, they probably know your passcode too. Change it, then see what to do if someone knows your iPhone passcode.

How do you stop face and fingerprint unlock for the night?

Both platforms can switch off biometrics until you next type your code, which is useful before you sleep somewhere you're unsure about.

On iPhone with Face ID:

  1. Press and hold the side button and either volume button for 2 seconds.
  2. When the sliders appear, press the side button to lock the iPhone.
  3. Apple says Face ID is enabled again the next time you unlock with your passcode.

On a Pixel:

  1. Press the Power and Volume up buttons at the same time.
  2. Tap Lockdown. Google says this turns off notifications, fingerprint or face unlocking and Extend Unlock on the lock screen, and only lasts until you next unlock.

If the person you're worried about is a partner or someone you live with and you feel unsafe, the National Domestic Abuse Helpline, run by Refuge, is free on 0808 2000 247. In an emergency, call 999.

Where Failshot fits

Your phone can't tell you whose face or finger unlocked it. Failshot photographs whoever unlocks your phone while Failshot is on, and the camera light shows whenever it takes a photo.

On iPhone, Apple doesn't let any app see the Lock Screen or use the camera in the background, so you turn Failshot on and lock the phone before you sleep. Whoever unlocks it lands in Failshot and is photographed. It doesn't photograph a wrong passcode at the iPhone Lock Screen. On Android, Failshot also photographs a wrong PIN, pattern or password at the real lock screen.

Switching Failshot off needs Face ID, your fingerprint or face on Android, or your own Failshot PIN plus your answer, never the phone's passcode. A wrong Failshot PIN takes another photo. When you switch it off yourself in the morning, the photo of your own unlock is deleted. Photos stay on your phone, with optional email alerts. Failshot is for your own device only, and it's coming soon to iPhone and Android.

Questions people also ask

Can someone unlock my iPhone with my face while I'm asleep?

Apple says Face ID recognises whether your eyes are open, which makes it more difficult for someone to unlock your iPhone while you're sleeping. That relies on Require Attention for Face ID being on, in Settings > Accessibility > Face ID & Attention.

Does Face ID work with your eyes closed?

Not with Require Attention for Face ID turned on. It's an accessibility setting, and Apple lets you turn it off if you find looking at the screen difficult. With it off, Face ID no longer needs your eyes to be open, so leave it on unless you need it off.

Can someone use my finger to unlock my phone while I sleep?

Fingerprint sensors check the finger, and Apple's and Google's pages don't describe a check that you're awake. If that's a worry, use Lockdown on a Pixel, or turn off fingerprint unlock and use your passcode or PIN at night.

Can my twin unlock my phone?

Possibly. Apple puts the chance of a random person unlocking Face ID at less than 1 in 1,000,000, but says it's higher for twins and siblings who look like you. Google says Pixel Face Unlock can be unlocked by someone who looks a lot like you, such as an identical sibling, and Samsung gives the same warning for twins.

How do I know if someone unlocked my phone while I was asleep?

Your phone won't say who unlocked it. iPhone Screen Time and Android Digital Wellbeing can show activity you don't remember. Our guide on how to know who unlocked your phone walks through both.

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