Smartphone owners are often faced with the need to accurately determine the display parameters of their device, be it to purchase protective glass, customize the interface, or check compliance with the stated characteristics. Screen size —this is not only the diagonal in inches, which is indicated in marketing brochures, but also the physical resolution matrices, as well as pixel density. Understanding these parameters is critical for those who are modifying the system or selecting content to view.
Standard methods allow you to quickly get general information, but they do not always give the full picture. Android Gives users several levels of access to technical information: from simple settings in the menu to deep system logs. In this article we will analyze all the methods, from elementary to advanced, so that you can get comprehensive data about your display.
It is worth noting that manufacturers often use different shells that can hide or modify standard paths to information. Screen resolution and the physical size may be displayed differently depending on the version of the operating system. Therefore, it is important to know several verification methods to ensure the reliability of the data received.
Using the standard settings menu
The most accessible way to get basic information about the display is the standard settings menu of your smartphone. Most manufacturers place model information and sometimes resolution information in the “About Phone” or “System Information” section. However, the exact diagonal in centimeters or inches is rarely indicated here; most often you will see only the marketing name of the model.
To obtain more detailed technical information, you must activate the hidden developer mode. This is a safe procedure that allows access to additional system parameters. Go to Settings → About phone and find the item “Build number” (or “MIUI Version”, “Software Version”). Click on it quickly 7 times in a row until a notification appears indicating that you have become a developer.
⚠️ Attention: Enabling developer mode gives access to critical system settings. Do not change the values in this menu if you are not sure of their purpose, as this may lead to interface instability.
After activation, a new section “For Developers” will appear in the main settings menu. Inside it you need to find the item “Minimum width” or “Screen resolution” (the name may differ depending on the shell). This often displays the current DPI (dots per inch) values and the actual pixel resolution that the system uses to render the interface.
Checking through the engineering menu and codes
The engineering menu is a hidden section of the system intended for testing equipment. It is accessed through a special set of characters in the Phone application (dialer). Enter the code ##4636## or #0#. If the code is suitable for your model, a service menu will open with various tests.
In this menu you can often find a “Device information” or “Version information” section, which contains detailed technical statistics. Not only the processor model and version are displayed here Android, but also the native resolution of the matrix. This value is the physical maximum that the screen supports, in contrast to the software resolution, which can be changed by the user. Unfortunately, many manufacturers, such asp>
Unfortunately, many manufacturers, such as Samsung or Huawei, block access to the engineering menu through standard dialing in global firmware versions. In such cases, the code will simply not work or will redirect to other functions. This is done for security purposes so that inexperienced users do not reset the sensor or color calibration.
What to do if the codes do not work?
If standard USSD codes do not open the menu, try downloading a special application from the Play Market that emulates these commands, for example, "Shortcut Master". It allows you to open hidden system activities without entering codes.
Using third-party diagnostic applications
The most convenient and informative way for the average user is to install a specialized application from the store Google Play. Such utilities read data directly from system files and display them in a convenient, structured form. The leaders in this category are applications CPU-Z, AIDA64 and Device Info HW.
After installation, for example, CPU-Zyou need to go to the “Device” or “Display” tab. Here you will see the full specification: physical size in inches (eg 6.5"), pixel resolution (eg 2400x1080), pixel density (DPI) and aspect ratio. This data is taken from the system build.prop file and is the most reliable.
- 📱 CPU-Z is a classic tool that shows detailed information about the processor, memory and display in real time.
- 📊 AIDA64 — provides an in-depth analysis of all components, including sensor temperatures and accurate matrix models.
- 🔍 Screen Test —a specialized application not only for viewing characteristics, but also for checking dead pixels and touchscreen.
It is important to understand that applications may show slightly different DPI values. This is due to the fact that Android uses logical. density for interface scaling, which may differ from the physical density of the matrix. For most tasks (purchasing film, setting fonts), the values shown by the application are sufficient.
Receiving data via USB debugging (ADB)
For users who need maximum accuracy and who do not want to install unnecessary applications, the ideal option is to use USB debugging. This method requires connecting the smartphone to a computer and having it. installed package ADB (Android Debug Bridge). It allows you to receive “raw” data directly from the display drivers.
First you need to enable “USB debugging” in the developer menu (as described above). Then connect the phone to the PC with a cable. Open the command line on the computer in the folder with ADB and enter the command to test the connection: adb devices. If the device is detected, you can request screen information.
adb shell wm size
adb shell wm density
Team wm size will return the physical and current screen resolution. The command wm density will show the current and physical pixel density (DPI). received via ADB are considered reference for this device.
☑️ Preparing to work with ADB
Table of main screen parameters
To make it easier for you to navigate the received data, we have compiled a table with an explanation of the main terms that you will encounter during diagnostics. Understanding the difference between these parameters will help avoid confusion when setting up the device.
| Parameter | Designation | What it means | Units of measurement |
|---|---|---|---|
| Resolution | Resolution | Number of pixels horizontally and vertically | Pixels (px) |
| Density | DPI / PPI | Number of dots per diagonal inch | Dots per inch |
| Diagonal | Size | Physical size visible area of the screen | Inches (inch) |
| Frequency | Refresh Rate | Number of picture updates per second | Hertz (Hz) |
Pay attention to the refresh rate parameter on modern flagships. support 90 Hz, 120 Hz and even higher. This value can also be checked via ADB command dumpsys SurfaceFlinger | grep "refresh" or in the display settings. High frequency makes the interface smoother, but consumes the battery faster.
The influence of cutouts and roundings on the usable area
In modern smartphones, the concept of “screen size” has become more complex due to the appearance of cutouts for the camera (notches), holes in the matrix and strongly rounded edges. Technically, the diagonal is measured at the corners of the visible rectangular area, but manufacturers often indicate the size of the full matrix, including those hidden by the frame. zones.
This means that the actual usable area for displaying content may be less than stated. The operating system Android compensates for this by creating virtual black bars or rounding the corners of the interface. Applications that require precise positioning (for example, AR games or drawing tools) may use coordinates without taking into account cutouts, which requires care.
⚠️ Attention: When purchasing protective glasses, pay attention to compatibility with your model. Due to the curves (“waterfalls”), the full glass may not stick at the edges or give a rainbow effect.
To accurately measure the diagonal in centimeters, use a regular ruler, placing it from corner to corner of the visible area, bypassing the frame of the case. 1 inch is equal to 2.54 cm.
Frequently asked questions (FAQ)
Why are there different DPI numbers in the settings and in the CPU-Z application?
This is normal. The settings often display the logical DPI, which is used for scaling fonts and icons. Applications like CPU-Z show the physical DPI of the matrix. The difference is due to the software add-ons of the shell manufacturer.
Is it possible to change the screen resolution via ADB?
Yes, it is possible. The command adb shell wm size 1080x1920 will change the resolution. However Changing the native resolution to a non-standard one can lead to incorrect display of the interface, the appearance of black bars or the touchscreen not working in certain areas. You can return the original value with the command adb shell wm size reset.
How to find the actual size in centimeters if the specification only contains inches?
Multiply the value diagonal in inches by 2.54. For example, a 6.5-inch screen is 16.51 cm diagonally. However, due to different aspect ratios (16:9, 19:9, 20:9), the height and width of the screen in centimeters will differ even with the same diagonal.
Does the design theme affect the screen size?
Themes change only the graphic style of the icons and the color scheme. They do not affect physical resolution or pixel density. However, some themes can change the scale of the interface, which visually makes the elements larger or smaller.
The fastest way to find out the exact characteristics of the screen without installing apps is to use the wm size command via ADB, if you have access to a computer.