Have you bought a used Xiaomi and questioned the seller's integrity? Or just want to know how many hours your smartphone has actually been running since it first turned on? The operating time is a key measure of wear and tear that directly affects battery life, processor performance and overall device stability. Unfortunately, this information is not available in standard MIUI settings, but it can be obtained in several ways, from hidden menus to technical utilities.
In this article, we will discuss 5 working methods, including ADB verification, engineering menus and specialized applications, which data is more accurate, how to interpret it correctly, and why some methods can show inflated or undervalued values, and how to distinguish real time from standby time, which is often presented as “working” by unscrupulous sellers.
1. Check through MIUI Battery (the easiest way)
If you don’t need high-precision data, just a rough estimate, start with the built-in MIUI tool. This method doesn’t require root rights or a PC connection, but shows the time of active use (screen is on) for the last charging cycle, rather than the overall performance of the smartphone.
How to check:
- 🔋 Open the Settings. → Battery.
- 📊 Slip on the consumption chart (at the top of the screen).
- ⏱️ At the bottom will appear the line "Use time" - this is the active experience for the current cycle.
⚠️ Warning: This metric is zeroed out after every full charge! It doesn't show the total device life since release, but only helps you estimate how much you've used your phone in the last day.
2. Engineering menu (#4636##) - hidden data
Xiaomi’s engineering menu includes advanced statistics, including processor and communication module lifetimes, but these data are not always accurate for estimating overall wear and tear, as they show performance of individual components rather than the device as a whole.
Instructions:
- Open the Phone app.
- Enter the combination: ##4636## (some models may not work).
- Go to the tab "Use statistics".
- Pay attention to the fields Time since boot (time since the last reboot) and Total uptime (total operating system running time).
| Parameter | What shows | Example of meaning |
|---|---|---|
| Time since boot | Time from last inclusion | 2 days, 3:45:12 |
| Total uptime | Total operating time of the OS (reset after reset) | 1500h 23m |
| Screen on time | Time with screen on (for the last cycle) | 4h 12m |
⚠️ Warning: Total uptime is reset after resetting settings or firmware! it can't be used to assess used phone wear.
Why does the engineering menu show inaccurate data?
3. ADB-commands: accurate workflow of the processor
For advanced users, the most reliable way is to use ADB (Android Debug Bridge), which shows the actual CPU life from the moment of first activation, which is not reset during updates (unless a full reset has been performed).
Step-by-step:
Enable USB debugging in Settings → About Phone → MIUI version (shap 7 times)
Connect your phone to your PC and confirm your trust in your computer
Download ADB Tools from Google
Open the command line in the folder with ADB-->
adb shell
cat /proc/uptimeYou'll get two digits back, one is the CPU's life in seconds since the last restart, the other is downtime. To get a general operating time, use the command:
adb shell
cat /sys/class/power_supply/battery/time_in_stateThis command will output an array of data about the time the battery spent in different states (charging, discharging, waiting), and summarizing the values, you get a rough run.
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If the team cat /proc/uptime returns a large number (for example, 10000000 So, if you're a second, it might mean that the meter is overflowing or has been reset, then try an alternative method through applications like AccuBattery.
4. Diagnostic applications: AccuBattery, CPU Monitor
If ADB commands seem complicated, use specialized applications that analyze data from sensors and system logs, providing a user-friendly interface for assessing wear.
Top.-3 apps:
- 🔋 AccuBattery - shows charging cycles, battery wear and approximate running time. Free version limited to 3 days' stats.
- 📊 CPU Monitor - monitors the load on the processor and the total core activity time.
- 🛠️ DevCheck – displays technical data, including the device’s operating time (Hardware section).
⚠️ Note: Apps can't get full-time data from the moment they're released -- they only show statistics for the period they're in use. For example, if you installed AccuBattery a month ago, it doesn't know what happened before.
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No Google Play app can tell you the exact time of your phone since it first turned on, and they only analyze the available logs that are reset or reset.
Serial number check (for new devices)
If you buy Xiaomi hand-held and want to check if it has been used, you can request serial number information through official channels, which only works for devices that have not been activated before (i.e. new).
How to check:
- Find the serial number in Settings → About Phone → General information or on the box.
- Go to the official Xiaomi checkout site.
- Enter the serial number and the captcha.
- The system will show activation status, and if the phone is already activated, you'll see the date of the first turn on.
🔍 What to do if a seller refuses to show a serial number? is a clear sign of fraud.The new Xiaomi always comes with an intact seal on the box and non-activated status.
Frequent Mistakes and How to Avoid Them
Many users confuse working hours and standby time, which leads to incorrect data, and these are the most common misconceptions:
- ❌ "Screen time = work-in" → Screen on time only shows active usage, not total operation of the device.
- ❌ "The data from the engineering menu is accurate" → Unless the phone has never been re-flashed, the counters will reset.
- ❌ "Apps show full wear and tear" → They only analyze available logs, which are limited to the last cycles.
🔧 How do you interpret data? Compare multiple sources:
If ADB shows 2,000 hours and AccuBattery shows 500, then the phone has often been rebooted or flashed.
- If the processor is running time (from /proc/uptime) significantly exceeds the screen time, the device worked in the background for a long time (for example, as a server or for mining).