These are the instructions to update stock firmware on Xiaomi Smartphone and tablets without using any flash tool.
Requirements: You need to have the official Xiaomi Firmware for your smartphone and tablets.
Update stock firmware on Xiaomi Smartphone
Download and install Xiaomi USB driver on your computer. If Xiaomi USB Driver is already installed on your computer then Skip this Step.
Download Xiaomi Stock Firmware (zip file) on your computer.
- Connect your Xiaomi Device to the computer and copy the zip file to your device.
- Once you have copied the zip file to the phone SD then disconnect it from the computer.
- Now, Open Tools Folder from the Launcher and Select Updater.
- Now, Hit the Menu Key on your Device and Select installation file.
Step 7: Now, Locate the zip file that you have copied to the Phone SD.
- Now, hit the update button to begin the update process.
- Now you will be able to see the update process.
- Once update process is completed, select reboot to finish.
 You can follow the above method to downgrade or update your Xiaomi Device. If in case you are on new firmware and want to downgrade, then you need to download the old firmware first then follow the above tutorial.
 Recommendation: Please take a backup of your device before updating your device using the above method. So, that you can recover your personal data when any thing wrong happens.
 Xiaomi Stock Firmware: If you are looking for the original firmware for your device, then head over to Download Xiaomi Stock Firmware page.
 Xiaomi USB Driver: If you are looking for the original USB Driver for your device, then head over to Download Xiaomi USB Driver page.
 Credits: The above guidelines are based on Xiaomi Update Package. So, Full credit goes to them for their brilliant efforts.