How to fully format the smartphone Xiaomi Redmi Note 9: 3 proven ways

Formatting Xiaomi Redmi Note 9 is a procedure that can be required in a variety of situations, from preparing the device for sale to fixing software failures. Many users confuse formatting with a normal reset, but these processes have key differences. Formatting involves completely cleaning the internal memory of the smartphone with the possibility of changing the file system, whereas reset simply returns the settings to factory, leaving the file structure unchanged.

In this article, we will discuss the three official ways to format the Redmi Note 9: through the Recovery Mode menu, using the Fastboot and through the Android settings. Particular attention will be paid to the nuances that even experienced users often miss – for example, how to choose the right file system (F2FS or EXT4) for optimal performance, or what to do if the smartphone does not turn on after formatting, and you will find answers to questions about data retention, unlocking the bootloader and compatibility with custom firmware.

Before you start, make sure you have a backup of all the important data. Formatting is an irreversible process that removes all the information from the internal drive, including photos, contacts and installed apps. If you plan to sell or transfer a smartphone to another person, we recommend further deleting your Mi Account account to avoid problems with the new owner activating the device.

Preparation for formatting: what to do in advance

While it seems simple, the Redmi Note 9 formatting requires a lot of preparation, and the first and most important thing is to back up your data. Even if you plan to use cloud services like Mi Cloud or Google Drive, local copying on your PC will be more reliable.

• 📸 Photos and videos – check folders DCIM Pictures and hidden directories of messengers (WhatsApp, Telegram).
• 📞 Contacts and Messages – Export them through Settings → Google → Backup or specialized applications like Super Backup.
• 🎮 Game saves – many mobile games (e.g. Genshin Impact or PUBG Mobile) link progress to your account, but some store data locally.
• 📁 Application files – some programs (e.g, 1Password or Notion) save data in their own folders on the internal drive.

The second is to check the battery power, make sure it's at least 50 percent charge level, and if the smartphone runs out during the formatting process, it can damage the system partition and the device's "brick," which will require flashing through the device. EDL-Prepare the regime. USB-cable (preferably original) and PC with Xiaomi drivers installed if you plan to use the Fastboot method.

The third step is to unlock the bootloader (if required). If you are going to install custom firmware after formatting, the bootloader must be unlocked.

fastboot oem device-info

In the answer, look for the line Device unlocked: true. If it is false, you will need to officially unlock through the Xiaomi website (the process takes up to 72 hours).

⚠️ Note: If you format your smartphone to be transferred to another owner, be sure to delete your Mi Account through Settings → Xiaomi account → Delete your account. Otherwise, the new user will not be able to activate the device without your login details.

Method 2: Formatting with Recovery Mode (without PC)

This method is suitable for most users, because it does not require a computer connection, it allows you to perform a complete reset with the formatting of the data partition, but does not affect the system files.

1. Turn off your smartphone. Press the Power and Volume buttons up for 10 to 15 seconds at the same time until the Mi logo and the Recovery menu appear.
2. Use volume buttons for navigation and power button for selecting a point. Select the language (usually English or Russian).
3. Go to Wipe Data → Wipe All Data. Confirm the action by selecting Confirm.
4. Wait until the process is completed (usually takes 1-3 minutes) and the words Data wipe complete will appear.
5. Go back to the main menu and select Reboot → Reboot to System.

This method does not change the file system (remains EXT4 or F2FS, depending on the firmware), but completely clears the data partition, including internal memory. If after a reboot the smartphone hangs on the Redmi logo for a long time, do not panic - the first download after formatting can take up to 10 minutes.

Backup copy of data created|Battery charge ≥50%|USB-Debugging is disabled (if not needed)|Mi Account deleted (when transferring device)-->

If you encounter a "No OS installed" error after formatting, it means that the system partition has been corrupted, in which case you will need to flash through Fastboot or Mi Flash Tool.

Method 2: Formatting via Fastboot (for power users)

This method provides more control over the process and allows you to change the file system or format individual partitions (for example, cache or vendor). ADB/Fastboot. Here's how to do it:

First, connect your smartphone to your PC in Fastboot mode:

1. Turn off the device.
2. Press the Nutrition + Volume down until the image of the rabbit appears in the eardress cap (Fastboot logo).
3. Connect your smartphone to your PC via USB.

Now open the command prompt (CMD) on your PC and execute the following commands in turn:

fastboot devices

(Checks that the device is detected. If the list is empty, re-install the drivers.)

fastboot erase userdata


fastboot erase cache




fastboot format:ext4 userdata

The last command formats the userdata partition into the EXT4 file system. For F2FS, use:

fastboot format:f2fs userdata

To fully format all sections (including the system) do:

fastboot erase system


fastboot erase vendor




fastboot erase product

⚠️ Note: Formatting the system partition will remove the firmware, and then you will need to flash it through the Mi Flash Tool or fastboot update!

Once completed, enter:

fastboot reboot

If you choose to format only the userdata partition, the smartphone will boot in its pure form, but with the firmware saved. If you format the system, you will need firmware.

Method 3: Formatting through Android Settings (soft reset)

This is not a full formatting solution, but it's often enough to fix software failures, it cleans the user's data, but it doesn't affect the system files and the file system, and it's good if you're not planning to install custom firmware or sell a device.

Instructions:

1. Open the Settings. → The phone.
2. Tap 7 times on the MIUI version to activate Developer Mode.
3. Return to Settings → Additional → For developers and enable USB Debugging (optional, but useful for diagnosis).
4. Go to Settings → System → Resetting settings.
5. Choose Delete all data and confirm the action.

It takes 5-10 minutes. Once you reboot, you'll get your smartphone in a post-purchase state, but with the firmware and file system saved, a method that doesn't delete files from the memory card (if it's installed), but cleans the internal drive.

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If after reset, the smartphone began to work slower, try to turn off animation in the developer settings (Settings → For developers → Window / Transition animation scale = Off).

5. How to recover data after formatting

If you forgot to back up, the chances of recovering the data depend on whether the information was overwritten after formatting.

Method 1: Recovery programs

• 🖥️ DiskDigger – works with internal memory of Android ROOT-PC access.
• 🖥️ Recuva – Suitable for recovering files from a memory card (if it wasn’t formatted).
• 📱 Undeleter – an Android application that requires ROOT-rights.

Method 2: Cloud services

Check if automatic backups have been enabled:

• 🌥️ Google Photos – Restore photos if sync is activated.
• 🌥️ Mi Cloud – can contain copies of contacts, notes and messages (if you have a Xiaomi account attached).
• 🌥️ WhatsApp Google Drive – WhatsApp chats are restored when the messenger is first launched after resetting.

Method 3: Contacting a Service Center

If data is critical (e.g., work documents or unique photos), you can contact the data recovery lab, the cost of the service starts at 5,000 rubles, but the chances of success depend on the degree of memory overwriting.

⚠️ Warning: Do not install new apps or copy files to your smartphone after formatting if you plan to recover data! Each new record reduces the chances of a successful recovery.

6. Frequent errors and their solutions

Even when following instructions, users often encounter problems, and consider the most common errors and ways to fix them:

If you encounter an error not described in the table, try finding a solution in the forums. 4PDA or XDA Developers, specifying the exact model of the smartphone (Redmi Note) 9 There are several modifications: merlin, merlin_in, merlin_eea).

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If the smartphone doesn't turn on after formatting, don't try to repeat the procedure many times. This can aggravate the problem. It's better to correctly reflash the device through the Mi Flash Tool once with the choice of the clean all option.

7. Formatting vs. resetting settings: what's the difference

Many users confuse the two processes, but they are fundamentally different:

• 🔄 Factory Reset: Deletes user data and applications. Does not affect system files and file system. Performs through Android or Recovery settings. Does not require a PC connection.
• 🗃️ Formatting: Completely clears selected partitions (e.g., userdata, system) and can modify the file system (EXT4 ↔ F2FS). Requires Fastboot or specialized utilities, often used before installing custom firmware.

For most tasks (removing lags, preparing for sale), a reset is enough.

• Install custom firmware (LineageOS, Pixel Experience).
• Switch to another file system.
• Removal of serious file system errors (e.g., "E:unknown volume for path [/data]")

FAQ: Answers to Frequent Questions