Flashing smartphone firmware Android at home is a task that frightens many users. Meanwhile, with the right approach and preparation, this process can become not only safe, but also useful: you will receive the latest version of the OS, get rid of factory software, or even bring a “brick” back to life after an unsuccessful update. However, it is important to understand that firmware is not just pressing a couple of buttons. This is a set of actions that requires attention to detail, understanding of terminology and preparedness for possible risks.

In this article we will analyze the entire process from start to finish: from choosing the appropriate firmware to restoring data after installation. You will learn what tools are needed for Samsung, Xiaomi, OnePlus and other popular brands, how to avoid beginner mistakes, and what to do if something goes wrong. We will pay special attention data security because incorrect actions can lead to irretrievable loss of photos, contacts and other important files.

Before you begin, answer two key questions: why you need firmware (updating, unlocking, customization) and Are you ready? to possible consequences such as loss of warranty or unstable operation of the device. If the answers are positive, welcome to the cat.

📊 Why do you want to flash Android?
Update the OS version
Install a custom one firmware
Remove bloatware
Restore brick
Other

1. Preparing for the firmware: what needs to be done before you start

The first and most important stage is preparation. Here 80% of success depends on how carefully you follow the preliminary steps. Start with data backup. Even if you plan a "soft" firmware without resetting the settings, there is always a risk of losing information. Use cloud services (Google Drive, Mi Cloud) or local copying to your PC via MTP or ADB.

The next step is to check compatibility. Make sure that the selected firmware is suitable for your smartphone model. For example, firmware for Samsung Galaxy S23 (SM-S911B) will not be suitable for Galaxy S23+ (SM-S916B), even if the difference is only one character. Look for official firmware on manufacturers' websites or trusted resources like XDA Developers, SamMobile (for Samsung) or Miui Downloader (for Xiaomi).

  • 📱 Find out the exact model of the device: go to Settings → About phone → Model or check the sticker under the battery (if removable).
  • 🔋 Charge the battery to at least 70%The firmware may take from 10 minutes to an hour, and discharging in the process will lead to a failure.
  • 🔌 Prepare a cable and a PC: use an original USB cable (Chinese "no-name" ones may not transfer data). Disable the antivirus on your computer - it may block the firmware tools.
  • 🔐 Unlock the bootloaderif you are planning custom firmware. Xiaomi this is done through Mi Unlock Tool, for Google Pixel —by the command fastboot flashing unlock.
⚠️ Attention: Unlocking the bootloader on some devices (for example, Huawei or Honor) may not be possible without an official code from the manufacturer. Check this point to beginning of the firmware.

Make sure the firmware and model are compatible|Make a backup of the data on your PC/cloud|Charge the phone >70%|Install drivers (ADB, Fastboot)|Disable antivirus on your PC|Download the firmware and tools (ODIN, Fastboot, SP Flash Tool)

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2. Selecting firmware: official vs custom

There are two main types of firmware: official (stock) and custom. The first ones are released by the manufacturer and guarantee stability, but often contain unnecessary software (bloatware). The latter are created by enthusiasts and offer more customization options, but may be less stable.

Official firmware is better to choose if your goal is to update to the latest version Android or recover from a failure. They can be downloaded from manufacturers' websites:

Custom firmware (for example, LineageOS, Pixel Experience, Havoc-OS) are suitable for advanced users who want:

  • 🔄 Install pure Android without manufacturer shells
  • 🆕 Receive updates longer than the brand offers
  • 🎛️ Customize the interface for yourself (themes, gestures, performance)

But remember: custom firmware often deprives you of the official warranty and may contain bugs.

Type firmware Pros Cons Recommendations
Official Stability, manufacturer support, OTA updates Bloatware, limited customization For beginners and restoration of functionality
Custom (AOSP) Pure Android, regular updates, flexibility Possible bugs, loss of warranty, difficult installation For experienced users who are ready to experiment
Custom (based on stock) Keeps branded features, but with improvements Fewer updates than AOSP For those who want to maintain brand functionality
⚠️ Attention: Firmware for MediaTekchipsets (for example, in budget ones Realme or Redmi) often require special tools like SP Flash Tool. For Qualcomm Snapdragon usually used fastboot or QFil. Please check this point before downloading!

3. Necessary tools: what to download and install

Depending on the brand and type of firmware, you will need different utilities. Here's a basic set for most scenarios:

  • 🖥️ ADB and Fastboot: universal tools for working with Android via the command line. Download Platform Tools from Google.
  • 📦 USB drivers: for Samsung — Samsung USB Driver, for MediaTek — MTK VCOM Drivers.
  • 🔧 Flashers:
    • ODIN - for Samsung
    • Mi Flash Tool - for Xiaomi
    • SP Flash Tool - for MediaTekdevices
    • Fastboot - universal for most brands
  • 📄 Firmware v format:
    • .zip — for custom firmware (installed via TWRP)
    • .tar/.md5 — for ODIN (Samsung)
    • .tgz or .img — for fastboot

For devices with an unlocked bootloader, you will also need custom recovery (for example, TWRP). It is installed via fastboot command: 

fastboot flash recovery twrp.img

fastboot boot twrp.img

Critical: If you are flashing a device with a locked bootloader (for example, a new Samsung or OnePlus), attempt to install a custom firmware without unlocking will lead to hard brick irreparable damage that cannot be treated even through a service center.

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Before the first firmware, practice on a virtual machine with Android-x86 or an old unnecessary phone. This will help avoid errors on the main device.

4. Step-by-step guide: how to flash Android

The flashing algorithm depends on the tool. Let's consider the three most common scenarios: through ODIN (for Samsung), through fastboot (universal) and through TWRP (for custom firmware).

4.1. Samsung firmware via ODIN. phone and move it to

  1. Download ODIN (version 3.14.4 or later) and firmware in the format .tar.md5.
  2. Run ODIN on behalf of the administrator.
  3. Turn off your phone and switch it to Download Mode: press Volume Down + Power, then Volume Up to confirm.
  4. Connect the phone to the PC. In ODIN a message should appear Added!! in the log.
  5. In the AP section, select the firmware file. If the firmware is multi-component, upload the files to BL, AP, CP, CSC.
  6. Click Start and wait for completion (the phone will reboot automatically).

4.2. Firmware via Fastboot (universal)

Suitable for Google Pixel, OnePlus, Xiaomi (with unlocked bootloader) and other devices on Qualcomm.

# Switch to fastboot-mode

adb reboot bootloader



Unlocking the bootloader (if necessary)


fastboot flashing unlock



Firmware (example for Pixel)


fastboot flash bootloader bootloader.img


fastboot reboot-bootloader


fastboot flash radio radio.img


fastboot reboot-bootloader


fastboot flash --slot=all image.zip


fastboot reboot

4.3. Installing custom firmware via TWRP

  1. Download the firmware in format .zip and place it on a memory card or phone memory.
  2. Boot into TWRP: turn off the phone, then hold down Volume Up + Power.
  3. Make backup the current firmware (option Backup to TWRP).
  4. Click Wipe → Advanced Wipe and check Dalvik, Cache, System, Data.
  5. Return to the main menu, select Install, specify the path to the firmware file and confirm installation.
  6. After completion, click Reboot System.
What to do if the phone is stuck on the logo after flashing the firmware?

If the device does not boot further logo (bootloop), try:

1. Go to recovery (Volume Up + Power) and do Wipe Cache/Dalvik.

2. Reflash the device, making sure that the firmware is suitable for your model.

3. via ODIN/fastboot.

5. Typical errors and how to avoid them

Even experienced users sometimes encounter problems when flashing. Here are the most common errors and ways to solve them:

  • 🚫 "Invalid IMEI" or network loss: occurs when flashing an incompatible mod or a damaged partition EFS. backup EFS or flash the original modem.
  • 🔄 Bootloop (cyclic reboot): usually due to incompatible or incorrect firmware wipeTry resetting the settings via recovery or reflash.
  • 🔌 "USB not recognized": check the cable, ports, drivers and disable the antivirus Sometimes changing the connection mode from MTP on PTP.
  • 🔒 "Device is locked" in fastboot: this means the bootloader is not unlocked. To Xiaomi you need to wait 7-15 days after linking your account to the device.
⚠️ Attention: If after flashing Samsung after ODIN an error appears SW REV CHECK FAIL, which means the firmware version is lower than the current one. Use a newer firmware or check the box Nand Erase All (risk of data loss!).
Error Cause Solution
FAILED (remote:'Flashing is not allowed') Bootloader locked Unlock via fastboot oem unlock or the official brand utility
E: Footer is wrong in TWRP The firmware file is damaged Download the firmware again, check the checksum (MD5)
The phone does not turn on after flashing Incompatible firmware or power failure Flash via EDL Mode (for Qualcomm) or contact service
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90% errors when flashing are associated with incompatibility between the firmware and device model or a violation of the sequence of actions. Always double-check the firmware file name and phone model!

6. Data recovery after flashing

If you made a backup before flashing, data recovery will not be difficult. However, even without a backup, there are chances to return some of the information:

  • 📱 Contacts and calendar: if synchronization with Google Accountwas enabled, the data will be restored automatically after logging in.
  • 📷 Photos and videos: check the folder DCIM on the memory card or use apps like DiskDigger (for internal memory you will need root access).
  • 💬 Messages: you can restore SMS via backup in Google Drive (if enabled) or apps like SMS Backup & Restore.
  • 🎮 Apps & Games: Google Play saves a list of installed applications. Go to Play Market → Library.

For a deep scan of the internal memory (if the phone turns on), use Dr.Fone or EaseUS MobiSaver. These apps work without root, but with root access the chances of recovery are higher. Remember: the less you use your phone after data loss, the more files you can recover.

⚠️ Attention: If you flashed a device with encrypted memory (for example, Pixel or OnePlus s Android 10+), data recovery without backup is practically impossible. Encryption is tied to the old password, which is reset during firmware update.

7. Firmware for different brands: features

Each manufacturer introduces its own nuances into the firmware process. Let's look at the key differences for popular brands:

Brand Tool Features Link to firmware
Samsung ODIN Requires files in the format .tar.md5. For new models, you need version ODIN 3.14+. SamMobile
Xiaomi Mi Flash Tool or fastboot You need to link your account to the device and wait for unlocking (7-15 days). Firmware comes in Fastboot and Recovery. Miui Downloader
Google Pixel fastboot Firmware is available in the form of factory images. Unlocking the bootloader erases all data. Google Factory Images
Realme/Oppo Oppo Flash Tool or fastboot Firmware often requires authorization through a brand account. For custom firmware, you need to unlock the bootloader. Realme Software

For devices on MediaTek (for example, Redmi Note series or Tecno) is often required SP Flash Tool. It is important to choose the right one scatter-file —it determines which sections to flash and in what order. An error in selecting a file can lead to damage IMEI or NVRAM.

How to flash a device without a PC?

Some brands (for example, Xiaomi or Samsung) allow you to install official updates via Local Update in the settings. To do this:

1. Download the firmware in format .zip to the memory card.

2. Go to Settings → About phone → System update → Three dots → Select firmware file.

3. Confirm the installation.

⚠️ The method works only for official firmware and does not require unlocking the bootloader.

8. Frequently asked questions (FAQ)

Is it possible to flash a phone without losing data?

Theoretically, yes, if you install the official update via OTA or Local Update. However, when changing the Android version (for example, from 12 to 13) or installing custom firmware data wipe is required. The exception is firmware marked no-wipe, but they are rare and can lead to bugs.

How to check if the bootloader is unlocked?

Turn off the phone and hold down the combination to enter in fastboot (usually Volume Down + Power). If at the bottom of the screen you see the inscription Unlocked or an open lock icon, the bootloader is unlocked. For Xiaomi the status can be checked in Settings → About phone → Mi Unlock status.

What is a "brick" and how to avoid it?

Brick - a state when the device does not turn on and does not respond to buttons. There are two types:

  • Soft brick: the phone vibrates, the screen lights up, but does not boot (for example, bootloop). It can be treated by flashing it.
  • Hard brick: complete lack of response to charging and buttons. Often irreparable without a soldering iron (the boot chip is damaged).

To avoid being bricked:

  • Do not interrupt the firmware (even if the process is frozen).
  • Do not flash files intended for another model.
  • Do not use unofficial tools (for example, "one-click flashers" from dubious sites).

Do I need to get root access for the firmware?

No, root it is not required for the firmware itself. However, it may be needed:

  • To backup the partition EFS (contains IMEI and network settings).
  • To restore data after flashing (apps like DiskDigger work more efficiently with root).
  • To install some modifications (for example, Magisk for system rights).

Getting root after custom OS firmware usually does not cause problems, but on stock firmware it can disrupt the operation of banking applications (due to SafetyNet).

How to return the official firmware after custom?

The process depends on the brand:

  • For Samsung: flash the stock firmware via ODIN with mark Home CSC (saves data).
  • For Xiaomi: use Mi Flash Tool with option clean all (erases everything).
  • For Google Pixel: flash factory image via fastboot with the flag -w (wipe).

After returning to stock, you may need to re-register the device in SafetyNet (for work Google Pay and banking applications). Magisk or utility Universal SafetyNet Fix.