Flashing firmware carries a risk of permanently damaging your device. Proceed at your own risk.
Downgrading an ASUS ZenFone 5 typically involves manually flashing an older firmware version. This process is most common for rolling back from Android 10 to Android 9 or moving from Lollipop to KitKat on older models. Zenfone 5 Firmware Downgrade
This is the standard official method for ZenFone 5 (ZE620KL) users wanting to downgrade from Android 10 to Android 9. Flashing firmware carries a risk of permanently damaging
This process will erase all data on your phone. Back up everything before starting. This process is most common for rolling back
Older versions (like the T00F/T00J) may require using a PC with ADB (Android Debug Bridge).
After the process finishes, perform a Factory Reset from the recovery menu to ensure system stability. Maintaining the Downgrade
Tap the and disable "Auto-download system update".