How to know exactly the release date of the Xiaomi smartphone: from the box to service codes

Buying a Xiaomi smartphone in the secondary market or even in the official store sometimes turns into a lottery: sellers can hide the real age of the device, and the boxes can be lost. The release date of the phone is critically important: it depends on the warranty period, battery status and even compatibility with the latest versions of MIUI. For example, models older than 2020 may not receive an update to Android 14, and the battery after 3 years of operation loses up to 30% of capacity.

In this article, we’ll look at 5 working ways to determine Xiaomi’s production date, from serial number analysis to hidden service menus, how to distinguish original devices from fakes, why the data on the box and settings may not match, and what to do if the phone is already unlocked or stitched with custom firmware. All methods have been tested on models from Redmi Note 10 to Xiaomi 14 Ultra.

1. Release date by serial number (S/N) — most accurate

The serial number (S/N) is a unique device identifier that encrypts the production date, factory code and model, and Xiaomi has 11-15 characters in it and is applied to:

• 📦 Box (barcoded sticker)
• 📱 Slot SIM-maps (under the lid)
• 🔋 Battery (on some models)
• 🖥️ Phone settings (Settings) → The phone. → General information)

Xiaomi’s serial number format has changed over the years, but since 2018, the standard has been in place: the first 4 digits after the letter prefix denote the year and week of release. KY3C203501234:

• 20 - 2020
• 35th - 35th week (late August)

Until 2018, Xiaomi used a different format, where the date was encoded in 3-4 characters.

• 604 in issue ABC604... - 2016, Week 4 (January 2016).
• 730 - 2017, 30th week (July 2017).

The POCO and Black Shark models can be reversed, first week, then year (e.g. 3520 = 35th week of 2020).

⚠️ Note: If the serial number on the box and in the phone settings do not match - this is a sign:

• 🔄 Reflashing the device (for example, from the global version to the Chinese version).
• 🛠️ Maternity replacement repairs.
• ⚠️ Counterfeiting (especially if the number starts with 000 or contains repeating characters).

☑️ Checking the Xiaomi serial number

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Take a photo of the number from the box and phone | Compare the first 4 digits after the prefix | Check date matching on the sticker and in the settings |Use online decoders (links below)

2. IMEI Date Determination: Does This Method Work?

IMEI (International Mobile Equipment Identity) is a 15-digit code that is assigned to each phone. Unlike the serial number, the IMEI does not contain direct release date information, but can indirectly indicate the age of the device through:

• 📡 Room range (in older models) IMEI It starts with 86, and the new ones with 89).
• 🔍 Databases (services such as IMEI.info or IMEI24 Show an approximate year of release on the model).

To find out about IMEI:

1. On the phone keyboard, type: *#06#.
2. Look at the settings → About the phone → Status.
3. On the box or under the battery (for models with a removable battery).

⚠️ Note: If you enter *#06#, you will see several IMEI (for example, for two SIM-check both cards. IMEI may indicate:

• 🔧 Substitution of motherboard (one) IMEI Original, second from the donor).
• 📱 Modular phone (e.g. Xiaomi Mix Fold with separate phone) IMEI screen-on).

3.Date on box and stickers: what to look for and where

The original Xiaomi box contains 3 key date tags:

1. Serial number sticker (usually at the end of the box) – the same label shows the date of production in YYYY-MM-DD or YY/MM/DD format.
2. Barcodes – the first 4 digits after the letter prefix (e.g. 69412352010...) may denote 2020, the 10th week.
3. IMEI sticker – sometimes contains the date of packaging (not to be confused with the date of manufacture!).

Examples of the location of labels on boxes of different series:

⚠️ If the box looks new but the date on it is older than 2 years, it may be:

• 📦 Repackaging (the seller replaced the box with a new one, and the phone is old).
• 🔄 Returned goods (the phone was in the warehouse and was unpacked).
• 🚨 Fake (box from another model).

💡

Take a picture of the box from all sides before buying it, which will help prove the date discrepancy when returning.

4.Service codes and hidden menus: how to find out the date without a box

If you don’t have a box but your phone is on, you can use Xiaomi’s service codes and hidden menus, which work even on locked devices (if emergency mode is enabled).

Method 1: Engineering menu (for Qualcomm processors)

1. Open the Phone app.
2. Enter the code: ##4636###.
3. Go to the tab Information about the phone.
4. Scroll to the Hardware Info block, there may be a Manufacture Date string.

Method 2: Testing menu (for Mediatek)

1. Enter the code: ##36446337##.
2. Choose Version.
3. Look for MF Date or Production Date.

Method 3: ADB-Team (for advanced users)

If you have a computer and USB debugging is enabled, plug your phone in and do:

adb shell getprop ro.boot.ddr_info

In the answer, look for the line. manufacture_date (format: YYYYMMDD).

💡

Service codes may not work on custom firmware or phones with an unlocked bootloader.

Verification by model and version of MIUI: indirect signs

If none of the above methods worked, you can approximately determine the age of the phone by:

• 📱 Models and its announcement date (for example, Xiaomi Mi 11 released in December 2020, Redmi Note 12 – in October 2022).
• 🔄 Versions MIUI (The first firmware indicates the minimum age of the device).
• 🔋 Battery state (in Settings) → Battery. → View Full Charge Capacity).

An example of decryption according to MIUI version:

⚠️ Note: If the phone is updated to the latest version MIUI, But the serial number indicates the old release date, which could mean:

• 🔧 Firmware via Fastboot (with complete data cleanup).
• 🛠️ Replacement of the motherboard (new chip, old battery).
• 🚨 Substitution IMEI (illegal practices blocked by operators).

6. Online services for verification: which are working in 2026

If manual methods seem complicated, you can use online services, but not all of them are accurate — some databases are rarely updated or contain errors.

• 🌍 IMEI.info – shows the date of release IMEI (precision ~80%).
• 🔍 SNDeeP.info – decrypts Xiaomi serial numbers (supports formats until 2023).
• 📦 CheckCoverage – Although it’s an Apple service, some merchants use it for authentication (not recommended).

🔹 How to use SNDeeP.info:

1. Enter the Xiaomi serial number in the field on the site.
2. Press Decode.
3. In the results, look for the Manufacture Date line.

⚠️ Note: Online services may be:

• 🔒 Keeping your data safe (IMEI, serial numbers) in their databases.
• 📉 Give inaccurate results for new models (e.g. Xiaomi 14 can be defined as Xiaomi 13).
• 🚫 Lock down IP frequent use (limited by 3-5 checks per day).

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Before using online services, disable VPN – some sites block requests from Russia and CIS countries.

FAQ: Frequent questions about Xiaomi release date