How to check Android bootloader lock or unlock status from Fastboot

Most Android smartphones allow you to check the status of bootloader via Fastboot commands. The commands may vary across different OEMs. So, while there’s not a comprehensive list, the command shared in this post should work for most users. It is tested to work on Nokia, OnePlus and Xiaomi smartphones.

Follow the steps below to check whether your Android phone’s bootloader is locked or unlocked.

  1. Ensure that ADB & Fastboot are installed on your PC along with the drivers.
  2. Boot your device into fastboot mode. For most OEMs, you will need to press and hold the power and volume down buttons together from power-off state.
  3. Run the following command in your fastboot terminal or CMD:
    fastboot oem device-info
  4. The result will give you details about your device, along with the bootloader status. True means that the device is unlocked.
    Here’s a sample response:

    PS C:adb> ./fastboot oem device-info
    ...
    (bootloader) Verity mode: true
    (bootloader) Device unlocked: true
    (bootloader) Device critical unlocked: false
    (bootloader) Charger screen enabled: true
    OKAY [ 0.005s]
    finished. total time: 0.006s

In newer phones you will be able to separately see the unlocked and critical unlocked. The difference between the two is that the critical protects the upper level partitions which are critical for the phone to boot. You generally do not need to mess with the critical partitions.

Cannot access fastboot? The easiest (and non-fastboot) method to check the lock status is from the developer options. The entry “OEM unlocking” will fade out when the bootloader is already unlocked. It will also display Bootloader is already unlocked.

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