Searching for a unique device identifier often becomes a necessity at the most inopportune moment, especially when you need to activate a warranty, register a gadget at a service center or unlock a Mi Account (SN) — It's a unique code that's assigned to each individual electronics instance in production, and it's what makes your smartphone different from thousands of others, even if they have the same color and memory. IMEI, tethered, SN-The code identifies the entire "iron" itself.
Users often confuse IMEI and SN, but to contact official support Xiaomi or to verify the authenticity of the device on the manufacturer's website, most often ask for a serial number. It is a combination of letters and numbers, the length and structure of which can vary depending on the year of release of the model and the assembly plant. Understanding where to look for this information saves time and nerves when you need to urgently confirm ownership of the device.
There are many ways to find out this code, from simply looking at the packaging to using hidden engineering menus and computer utilities. The serial number on the box and in the system must match - this is the main criterion for verifying the originality of the device. In this article, we will discuss in detail all available methods, including those that work even if the smartphone screen is broken or the device does not turn on.
Search SN-code on the packaging and body of the device
The easiest and most obvious way to forget about it in a hurry is to look at the original box, and there's always a sticker on the side or the end of the cardboard packaging with the technical information. IMEI (often in two copies for two SIM-map), MAC-address and the Serial Number you're looking for, usually signed as "S/N" or "SN". This method is ideal if the smartphone is not unpacked or, conversely, has already been sold, and the box is carefully stored.
If the box is lost, it is worth looking carefully at the back cover of the gadget. On many modern models of Xiaomi, Redmi and POCO, the information is printed in laser engraved in small print at the bottom of the case or under the logo. However, in recent versions of devices, manufacturers increasingly refuse to duplicate data on the case, leaving only a certification mark, so this method does not work for all models.
- 📦 Find the white sticker on the end of the box and look for the line "S/N".
- 🔍 Inspect the back cover of the smartphone in good lighting, perhaps the text is struck with a laser.
- 📱 For devices with removable battery (old models), the label is under the battery.
⚠️ Warning: If you buy a used device without a box, and the seller claims that he threw the box away, but there is no engraving on the case, this is a reason to be wary. SN It may indicate a replacement of the body or re-adjustment.
It is also important to note that on some global versions of smartphones, the information on the box can be duplicated in several languages, but the code itself always remains the same. If the sticker on the box looks slapped, has opening marks or the font is different from the standard font Xiaomi, this can be a sign of a restored device or refinished product.
Checking the serial number in Android settings
If you have a device in your hand and it's functional, the quickest way to look at the system menu is to look at it, and the path to information may vary slightly depending on the version of the MIUI shell or HyperOS, but the logic remains the same. You need to go to Settings, then select About, and the menu that opens will show you basic information about the model, the Android version, and most importantly, a unique identifier.
In some firmware versions, the serial number is hidden inside All Features or MIUI Version. This requires a few quick taps on the line with the software version to open the extended menu, where, among the technical data, the line you are looking for may be called "Serial Number" or "SN." This is the standard procedure for accessing engineering information.
You should not ignore the possibility of copying data. In modern shells Xiaomi, when you press a line with a number long, a pop-up message often appears "Copied to the clipboard." This is convenient if you need to immediately insert the code into a form on the site of the service center, eliminating the risk of error when manually entering.
- 📲 Go to the Settings path → The phone.
- 👆 Make a few quick taps on the item "Version" MIUI" or "All characteristics".
- 📋 Use long-press to copy the code to the clipboard.
It should be noted that in some custom firmware or on devices with an unlocked bootloader, the display of this information can be changed by the developers of the modification. In standard stock firmware, the data is always available to the user without root rights.
Use of the engineering menu and USSD-code
For more in-depth diagnostics and technical information, there is an engineering menu, which is a hidden part of the system, designed for technicians, but accessible to ordinary users. To get there, you need to open the Phone app and enter a special code. For Xiaomi devices, the most versatile is the code # # # #6484## or ##4636##.
Once the last digit is entered, the code is activated automatically, and the CIT (Customer Integration Test) menu or test menu will appear on the screen. Depending on the menu version, the serial number information can be located in the "Version", "Status" section or displayed at the very top of the list, and you can also check the health of all sensors, screen and communication modules.
##6484##The code you enter opens up a diagnostic tool where SN is often duplicated in the "Device Info" block. This is especially useful if the standard settings menu is unstable or hangs. The engineering menu works at the system level, below the user interface, so it is available even in some software failures.
What if the code doesn't work?
⚠️ Warning: Be careful in the engineering menu. Changing the settings in the sections marked as "Debug" or "Network" without understanding their purpose can lead to signal loss or malfunction of the radio module.
Searching through the ADB command line (for advanced users)
If the smartphone screen is broken and does not respond to touch, but the device is turned on and determined by the computer, debugging via USB will come to the rescue. This will require installing Xiaomi USB Driver and the ADB utility on the PC, which requires pre-activating the USB Debugging mode in the Developer menu, which is activated by seven times pressing the build number in the About Phone menu.
Connect your smartphone to your computer with a cable, open the command line (CMD) or terminal in the folder with ADB. Enter the command to get all the properties of the device. Android stores the serial number in a variable environment that you can access directly, which is the most reliable way for blind devices with a working system.
adb shell getprop ro.serialnoOnce you enter the command and press Enter, the server will return the clean serial number without the unnecessary characters in response to the request. If the getprop command does not return the result, you can use the more general command adb shell properties and search the output line [ro.serialno]: [your number].
- 💻 Connect your phone to your PC and make sure that debugging mode is activated.
- ⌨️ Enter adb shell getprop ro.serialno in the terminal.
- 📝 Copy the response for use in warranty cases.
☑️ Preparation for work with ADB
Authentication through the official website
Once you have found the code, it needs to be verified. Xiaomi's official portal provides a service to verify the authenticity of the device. Go to the Mi Account authorization page or the special warranty verification section. By entering the serial number and captcha, the system will tell you whether such a device exists in the manufacturer's database and when it was activated.
This move is critical when buying a smartphone from hand or unverified stores. If the site says "Serial number not found", it could mean that the device was intended for the domestic market in China (the Chinese version) and does not have a global registration, or worse, you have a clone with an IMEI/SN interrupted.
| Status on the site | Meaning | Action |
|---|---|---|
| Valid / Active | The device is original, the warranty is active | Nothing to do. |
| Not Found | No data in the database (China or fake) | Check the IMEI separately |
| Expired | The warranty period has expired | Check the date of purchase |
| Invalid Format | Data entry error | Recheck the symbols |
Note that the database may be updated with a delay. If you have just bought a new smartphone, information about it can appear on the site 2-3 days after the first activation and login.
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Even if the site shows the status of "Active", it is the date on the check that is the priority for service centers when calculating the warranty period if the activation was later than the actual purchase.
What to do if the serial number is not read or lost
When stickers are erased, the box is lost and the menu is not opened, it seems deadlocked, but there are options. If the phone has any response to the connection to the PC, you can try to read the system log files through specialized utilities like Mi PC Suite (official, though rare now) or third-party tools like Mi Flash in check mode.
In extreme cases, if a device requires flashing, the Mi Flash Tool, when connecting a smartphone in Fastboot mode (clamping down the volume button when turned on), displays a unique device identifier at the top of the interface, which often coincides with or contains a part of the serial number, this is the last frontier before accessing the service.
⚠️ Note: Fastboot mode allows you to make changes to partitions of memory. If you are not sure about your actions, do not press the "Flash" button in the Mi Flash program, limit yourself to just visual check of the displayed. ID.
If nothing works and the device needs to be delivered under warranty, Xiaomi authorized service centers can conduct internal diagnostics using IMEI, which is tightly tied to the motherboard. Based on IMEI, engineers can sometimes restore the chain and find the corresponding SN in their internal databases, although this takes longer.
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The serial number is your device's passport, and save a photo of the box and the check immediately after you buy it so that if your screen or system breaks, you can prove ownership.