How to know exactly the release date of the Xiaomi smartphone: from serial number to hidden menus

Knowing the exact date of Xiaomi’s smartphone production is critical when buying a used device, checking warranty or evaluating battery wear. The manufacturer does not always specify the year of release on the box, and sellers can deliberately hide the real age of the phone. Meanwhile, even within the same Redmi Note 10 or POCO X3 model, devices of different batches can differ in build quality, firmware version and battery life.

In this article, we will discuss all the official and hidden ways to determine the date of manufacture of a Xiaomi smartphone – from decrypting the serial number to engineering codes. You will learn what methods work for models 2020-2026, how to distinguish the original from a fake by production date, and why some methods stopped working after the updates to MIUI 14.

⚠️ Warning: The date on the box and in the phone settings may not match! The manufacturer sometimes uses old packages for new batches of devices. Always double-check the information with at least two methods.

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

The serial number (S/N) is your smartphone’s unique identifier, which contains coded production date information, and on Xiaomi devices, it consists of 14–16 characters, where the first 4–6 digits indicate the week and year of release.

To find the serial number:

1. Go to Settings → About the phone → General information.
2. Scroll down to Serial Number (or Serial Number).
3. Write down or copy the combination.

The serial number format of Xiaomi may vary depending on the year of release:

• 📅 Old format (until 2019): YYYYWWXXXXXX, where YYYY — year, WW — week-long.
• 📅 New format (2020–2026): WWYYXXXXXXXX, where WW — week-long, YY — last two-digit.

An example of decryption:

Serial number: 2305A1BCD123456


23 → Week 23 (June)




05 → 2005? No! This is 2020 + 5 = 2026 (but since the current year is 2026, it's more like a mistake - right: 2020 + 05 = 2026 doesn't exist, so the format is different).




Correct interpretation for the new format:




23 → Week 23 (June)




- 05 → 2026? No, it's 2020 + 5 = 2026 (error). Actually: the first two digits after the letter are a year (05 = 2026, but it's a future year, so the number is fake or not from Xiaomi).

⚠️ Note: If the decryption turns out to be a year later than the current one (for example, 2026 when checked in 2026), this is a sign of a fake.

💡

If the serial number starts with letters (e.g., M2004...), it's a device model, not a date. Look for a digital block after a dash or a space.

2.IMEI Test: Does This Method Work for Xiaomi?

IMEI (International Mobile Equipment Identity) is another unique identifier that can theoretically contain production date information, but Xiaomi does not use this method for all models and often produces inaccurate results.

How to check:

1. Dial on the phone keyboard *#06# - a window with IMEI will appear.
2. Write down the first 8 digits (e.g., 86372904).
3. Use online services like IMEI.info or IMEI-Number.com.

Problems with method:

• ❌ Not all services support Xiaomi: Many databases are focused on Samsung or Apple.
• ❌ IMEI It may be interrupted: on used phones IMEI Sometimes they change the data, which distorts the data.
• ❌ No guarantee of accuracy: even the original IMEI It can show the date of production with error. ±3 months.

🔍 Alternative: If IMEI If you don't get it, try typing it on the official Xiaomi Verify website.The service checks the authenticity of the device, but doesn't always show the date.

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

On the original packaging, Xiaomi’s production date can be listed in several places:

1. Barcode on the side of the box: Under it, the month and year are often printed in MM/YYYY or YYYY-MM format.
2. Back Sticker: Look for lines like MFD (Manufactured Date) or DATE.
3. QC-Sticker (quality control): Small white sticker with numbers – the first 4-6 characters can indicate the date.

Examples of markings:

⚠️ Note: If the date on the box and the serial number of the phone diverge by more than 3 months, this may mean:

• 🔄 The device was in storage (possibly with a discharged battery).
• 🚨 Box from another phone (sign of counterfeit or repair).
• 🔧 The phone was returned to the service center and repackaged.

4 Hidden Engineering Menus: How to Find a Date Through Test Mode

Xiaomi smartphones have hidden service menus that sometimes display a production date, a method that doesn’t work on all models, but could be useful for 2018-2022 devices.

Instructions for entering the engineering menu:

1. Open the Phone app.
2. Enter the combination: ##4636###.
3. Go to the tab Information about the phone.
4. Look for Date of Manufacture or MFG Date.

Alternative codes for new models:

• 📱 ##284## - Camera test (sometimes showing build date).
• 📱 ##6484## - information about the module MTK (for MediaTek processors).
• 📱 ##64663## - hardware data (may contain date).

🔧 If the menu doesn't open:

• Try to clean it up. SIM-map and repeat code entry.
• On some MIUI 13+ firmware, the engineering menus are blocked.
• Use applications like MTK Engineering Mode (MediaTek only).

5. Check through official Xiaomi services

Xiaomi provides several official methods of authenticating the device, which sometimes indicates the date of production.

Method 1: Mi Verify Service

1. Go to https://www.mi.com/global/verify.
2. Enter. IMEI, S/N or scan QR-box-code.
3. If the device is original, the system will show the model and the activation date (not always the same as the production).

Method 2: Appendix Mi Account

• 📱 Get in to Mi Account. → Devices.
• 📱 Choose your smartphone – sometimes the details are specified First Activation Date.
• 📱 If there is no date, try syncing your data to the cloud.

⚠️ Note: Xiaomi’s official services may not show a production date for devices purchased outside of official stores (e.g., AliExpress or Amazon.

6.Indirect signs: how to determine the age of the phone without an exact date

If none of the methods worked, estimate the age of the device by indirect signs:

Battery and wear:

• 🔋 Enter the code #4636 in the engineering menu## → Battery information. Compare Level (current charge) and Health (health). If health is below 85%, phone is over 2 years old.
• 🔋 Use the AccuBattery app – it shows the number of charging cycles (more than 500 cycles) = 1.5–2 years of operation).

Firmware and updates:

• 📲 Go to Settings. → The phone. → System Update: If the last update is dated 2021 and the model supports MIUI 14, the phone's definitely old.
• 📲 Check out the Android version: if Android 10 is on the flagship of 2022 – it’s suspicious.

External signs:

• 🔍 Inspect the box: if it is yellowed or has crevices, the device is more than 1-2 years old.
• 🔍 Check out the configuration: the old Xiaomi models went with power supplies on 10W, new 33W/67W.

💡

Even if you haven’t found the exact production date, a combination of indirect features (firmware + battery + box) allows you to determine the age of the phone with an error of ±3 months.

FAQ: Frequent questions about Xiaomi's production date