Android: How To Programmatically Access The Device Serial Number Shown In The AVD Manager (API Version 8)


Answer :

This is the hardware serial number. To access it on

  • Android Q (>= SDK 29) android.Manifest.permission.READ_PRIVILEGED_PHONE_STATE is required. Only system apps can require this permission. If the calling package is the device or profile owner then the READ_PHONE_STATE permission suffices.

  • Android 8 and later (>= SDK 26) use android.os.Build.getSerial() which requires the dangerous permission READ_PHONE_STATE. Using android.os.Build.SERIAL returns android.os.Build.UNKNOWN.

  • Android 7.1 and earlier (<= SDK 25) and earlier android.os.Build.SERIAL does return a valid serial.

It's unique for any device. If you are looking for possibilities on how to get/use a unique device id you should read here.

For a solution involving reflection without requiring a permission see this answer.


Up to Android 7.1 (SDK 25)

Until Android 7.1 you will get it with:

Build.SERIAL

From Android 8 (SDK 26)

On Android 8 (SDK 26) and above, this field will return UNKNOWN and must be accessed with:

Build.getSerial()

which requires the dangerous permission android.permission.READ_PHONE_STATE.

From Android Q (SDK 29)

Since Android Q using Build.getSerial() gets a bit more complicated by requiring:

android.Manifest.permission.READ_PRIVILEGED_PHONE_STATE (which can only be acquired by system apps), or for the calling package to be the device or profile owner and have the READ_PHONE_STATE permission. This means most apps won't be able to uses this feature. See the Android Q announcement from Google.

See Android SDK reference

Best Practice for Unique Device Identifier

If you just require a unique identifier, it's best to avoid using hardware identifiers as Google continuously tries to make it harder to access them for privacy reasons. You could just generate a UUID.randomUUID().toString(); and save it the first time it needs to be accessed in e.g. shared preferences. Alternatively you could use ANDROID_ID which is a 8 byte long hex string unique to the device, user and (only Android 8+) app installation. For more info on that topic, see Best practices for unique identifiers.


Build.SERIAL can be empty or sometimes return a different value (proof 1, proof 2) than what you can see in your device's settings.

If you want a more complete and robust solution, I've compiled every possible solution I could found in a single gist. Here's a simplified version of it :

public static String getSerialNumber() {     String serialNumber;      try {         Class<?> c = Class.forName("android.os.SystemProperties");         Method get = c.getMethod("get", String.class);          serialNumber = (String) get.invoke(c, "gsm.sn1");         if (serialNumber.equals(""))             serialNumber = (String) get.invoke(c, "ril.serialnumber");         if (serialNumber.equals(""))             serialNumber = (String) get.invoke(c, "ro.serialno");         if (serialNumber.equals(""))             serialNumber = (String) get.invoke(c, "sys.serialnumber");         if (serialNumber.equals(""))             serialNumber = Build.SERIAL;          // If none of the methods above worked         if (serialNumber.equals(""))             serialNumber = null;     } catch (Exception e) {         e.printStackTrace();         serialNumber = null;     }      return serialNumber; }

I try to update the gist regularly whenever I can test on a new device or Android version. Contributions are welcome too.


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