How to know exactly the year of production of Xiaomi device: from smartphone to smart light bulb

Determining the year of Xiaomi’s production is a critical step before buying a used device, warranty repairs or installing custom firmware. Even in new boxes, there may be stale devices with outdated firmware or a discharged battery. The manufacturer does not always specify the date of production on the package, and in the system settings this information is hidden behind encrypted codes.

In this article, we’ll look at all the official and alternative ways to verify a year of release, from decrypting a serial number to analyzing hardware tags on the board. We’ll focus on the nuances for different categories of technology: smartphones (Redmi, POCO, Mi), smartwatches (Mi Band, Watch), routers and smart home devices, you’ll learn how to distinguish a 2023 device from a relabeled 2021, and why some methods don’t work for all models.

1. Decoding of the serial number (S/N) — universalism

The serial number is the main identifier of the device, which contains encrypted information about the date of production. Xiaomi S/N format depends on the year of production and manufacturer. Classic structure for smartphones (until 2021): ZDX02****, where:

• 🔢 The first 3 characters are the factory and model code (e.g, ZDX — China factory for Redmi Note line).
• 📅 4-Symbol: Year of production (digit) 9 = 2019, 0 = 2020, 1 = 2021 etc.).
• 📆 5th and 6th characters - week of release (01 to 52).

For devices 2022 In the past year and years, Xiaomi has moved to 12-signifier S/N, where the date is coded differently, like in a room. 22071A*:

• 📌 22nd year of production (2022).
• 📌 07 - July (month).
• 📌 1-week of the month.

⚠️ Note: Serial numbers of devices produced for the Indian market (POCO), They can use reversed date order, for example, 2007 into S/N July 2020, not 2020 year, 7 week-long.

2.IMEI Verification: Does it work for the production date?

IMEI (International Mobile Equipment Identity) is a unique identifier for a smartphone, but it does not contain direct release date information, but IMEI can indirectly determine a year by:

1. Online services like IMEI.info or SNDeep, which decrypt Range Date, the approximate activation period of the first SIM-map.
2. Operator databases if the device has been previously used (owner's consent is required).

🔍 How do you know? IMEI:

• 📱 Dial on the phone keyboard *#06#.
• 📄 Look at the sticker under the battery (for removable battery devices).
• 📦 On a box under a barcode.

⚠️ Note: If the service shows "Date Approved" (certification date), it's not the year of production! For example, Redmi Note 10 Pro is certified in 2020, but was released until 2023.

💡

If the IMEI starts with 86, the device is assembled in China; 35 is in Europe or India. This does not affect the date, but helps to identify "gray" shipments.

3. Hardware tag analysis (for advanced users)

On the motherboard of any Xiaomi device, there are sensors of production — fine text next to the chips.

• 🔧 Deconstructing the device (requires skills and tools).
• 📸 Through the macro photo of the lens of the main camera (light up with a flashlight).

Look for the marker.

🔎 Where to find:

• 📱 Smartphones: near a processor or memory module.
• ⌚ Smartwatches: on the back of the board under the battery.
• 📡 Routers: on a metal screen Wi-Fi module.

4. Checking through MIUI: Hidden menus and engineering codes

MIUI firmware contains the device's assembly date information to find it:

1. Open the Settings app → The phone.
2. Tap 7 times on the MIUI version to activate the developer mode.
3. Back to Settings → Additionally. → For developers.
4. Find the kernel version or build number – there may be a date in YYYYMMDD format (for example, 20230515 = May 15, 2023).

📌 Engineering codes for verification:

For smartphones:
##4636## → Phone Information → Software Assembly Date
#225## → Calendar of production (not working on all models)



For the smartwatch (Mi Band):




In the Mi Fit app, go to Device → Device → About → Firmware version – the last 4 digits often indicate the compilation date.

⚠️ Warning: The date of the software build may not coincide with the date of production of the device! POCO X3 The Pro, released in March 2021, could receive a firmware update in June 2021 – the menu will indicate a later date.

5.Official sources: warranty card and Xiaomi support

If the device is bought new, check:

• 📄 Warranty card: the date of sale must be no later than 6-12 months from the date of production (depending on the model).
• 📧 Electronic Warranty: Link your device to your Mi Account on account.xiaomi.com – your device profile may display the activation date.
• 📞 Call for Support: Provide Support S/N and IMEI shape mi.com/support (The answer comes in the course 3–5 days).

💡 Nuance: For devices purchased on AliExpress or Gearbest, the date on the warranty card may be forged!

⚠️ Note: If Xiaomi support refuses to provide a production date, refer to GOST R 51772-2001 (for Russia or EU Directive 2019/771 (EU) – these regulations require the manufacturer to disclose the release date at the request of the consumer.

Alternative methods: from database to physical inspection

If the standard methods do not work, try:

• 🔍 Serial Number Databases: SNDeep – Supported by Xiaomi, Redmi, POCO. IMEI24 — smartphone IMEI.
• 📦 Box and components: The label of the power adapter may indicate the date of production (format) YYWW, for example, 2135 = 2021, 35 On the cable. USB sometimes marked in format MM-YYYY.
• 🔋 Battery: The smartphone battery usually has a date sticker in format YYYY-MM-DD. For the Mi Band and Watch, the date can be engraved on the battery case.

🔧 Physical examination:

• 🔍 Look at the state of sealing gums (for waterproof models): if they turn yellow or lose elasticity, the device is more than 2-3 years old.
• 🔋 Evaluate battery wear through the AccuBattery app – if capacity has dropped below 80%, it is likely to be the device 3.+ year-end.

💡

The most reliable way is to combine serial number + battery dates + check through an engineering menu. One method can give inaccurate results!

FAQ: Frequent questions about Xiaomi's production date