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Many smartphones include special dialer codes that can display useful technical information, open diagnostic menus, or provide device identifiers. These codes are commonly used by technicians and developers for troubleshooting and testing. However, not every code works on every phone, as support depends on the manufacturer, model, Android version, carrier, and region.
Only use codes from trusted sources. Some service codes can reset settings or erase data on certain devices. Avoid entering unknown or unverified codes.
What Are Phone Dialer Codes?
Phone dialer codes, sometimes called USSD codes or MMI codes, are special character sequences entered in the phone app. Some are standardized, while others are created by individual manufacturers such as Samsung, Xiaomi, Google, Motorola, OnePlus, and others.
Many useful codes are read-only and simply display information about your device without making any changes.
Most Useful Phone Codes
| Code | Function | Supported Devices |
|---|---|---|
| *#06# | Display the IMEI number of the phone. | Almost all phones |
| *#07# | Display the SAR (Specific Absorption Rate) information, if supported. | Many modern smartphones |
| *#*#4636#*#* | Testing menu with battery, Wi-Fi, and network information. | Many Android devices (not all) |
| *3001#12345#* | Field Test Mode for cellular information. | Many iPhone models |
1. *#06# – Check Your IMEI Number
This is the best-known phone code and works on nearly every mobile phone. It displays your phone's unique IMEI (International Mobile Equipment Identity), which can help identify the device when contacting your carrier or manufacturer.
You can also find the IMEI in your phone's Settings menu or on the original device packaging.
2. *#07# – View SAR Information
On supported devices, this code displays information about the phone's radio frequency exposure (SAR). Availability varies by manufacturer and software version.
3. *#*#4636#*#* – Android Testing Menu
Many Android devices recognize this diagnostic code. It may display battery details, network information, Wi-Fi status, and usage statistics. Some manufacturers disable this menu, so it is not universally available.
If this code does not work, it usually means the manufacturer has removed or disabled the testing menu.
4. *3001#12345#* – iPhone Field Test Mode
Many iPhone models provide a Field Test Mode that displays advanced cellular network information. The available data depends on the iPhone model and iOS version.
Field Test Mode is primarily intended for diagnostics and network analysis rather than everyday use.
Useful Phone Codes for Popular Manufacturers
In addition to universal dialer codes, some smartphone manufacturers include diagnostic or service menus for technicians. These menus are not available on every device, and many newer software versions restrict access for security reasons.
| Brand | Diagnostic Code | Availability |
|---|---|---|
| Samsung | *#0*# | Many Galaxy devices |
| Xiaomi | *#*#6484#*#* | Many MIUI/HyperOS devices |
| OnePlus | Engineering menus vary by model | Limited availability |
| Motorola | Model dependent | Limited availability |
| Google Pixel | Most diagnostics are in Settings | No universal code |
Samsung Test Mode
Many Samsung Galaxy smartphones support the code *#0*#, which opens a hardware diagnostic menu. Depending on the model, you may find tests for:
- Display colors.
- Touchscreen.
- Speaker.
- Vibration.
- Cameras.
- Sensors.
- Receiver.
This menu is commonly used by service technicians to verify that hardware components are functioning correctly.
Xiaomi Hardware Test
Many Xiaomi devices recognize *#*#6484#*#*, opening a diagnostic interface with hardware tests such as the battery, sensors, touchscreen, and charging components. Availability depends on the software version.
If the code does not work, your phone model or firmware may not support it.
What Information Can These Codes Reveal?
| Information | Available on Some Devices |
|---|---|
| IMEI Number | ✔ |
| Battery Information | ✔ |
| Network Details | ✔ |
| Wi-Fi Status | ✔ |
| Sensor Tests | ✔ |
| Touchscreen Test | ✔ |
| Camera Test | ✔ |
| Display Test | ✔ |
Most of these menus are intended for diagnostics and hardware verification. They generally do not unlock hidden features or improve device performance.
Common Myths About Secret Phone Codes
- ❌ One code works on every phone.
- ❌ Secret codes can permanently speed up any device.
- ❌ Hidden codes unlock premium features for free.
- ❌ All internet lists of dialer codes are safe to use.
- ❌ Every Android manufacturer uses the same engineering menu.
Avoid entering unknown service codes copied from social media or unverified websites. Some codes may reset settings or perform maintenance actions depending on the manufacturer and software version.
When Are These Codes Useful?
- Checking the IMEI before buying a used phone.
- Testing hardware after a repair.
- Diagnosing touchscreen or display issues.
- Viewing network information.
- Verifying battery and sensor operation.
- Troubleshooting connectivity problems.
If you suspect a hardware problem, using the manufacturer's built-in diagnostic tools is often faster than installing third-party testing applications.
Frequently Asked Questions (FAQ)
Do secret phone codes work on every smartphone?
No. Some codes, such as *#06#, are supported on nearly all phones, while many diagnostic and engineering codes depend on the phone manufacturer, software version, region, and mobile carrier.
Can phone dialer codes damage my device?
Informational codes are generally safe. However, some manufacturer-specific service codes may reset settings or perform maintenance actions. Only use codes from trusted documentation.
Does *#06# track my phone?
No. The code simply displays your phone's IMEI number. It does not enable tracking or change any settings.
Why don't some codes work on my phone?
Manufacturers often disable or remove engineering menus for security reasons. Some codes are also limited to specific models or Android versions.
Best Practices When Using Phone Codes
- Only use codes published by your device manufacturer or trusted technical sources.
- Do not expect every code to work on every model.
- Avoid codes that promise to unlock paid features or "boost" performance.
- If a code opens a diagnostic menu, avoid changing settings unless you understand their purpose.
- Keep your device updated to benefit from the latest security improvements.
| Safe Code | Purpose | Risk Level |
|---|---|---|
| *#06# | Display IMEI number | None |
| *#07# | View SAR information (if supported) | None |
| *#*#4636#*#* | Diagnostic information (supported Android devices) | Low (view information only) |
| *3001#12345#* | iPhone Field Test Mode | Low |
If your goal is to check battery health, storage usage, or device performance, the built-in Settings app often provides the safest and most accurate information without needing special codes.
Conclusion
Phone dialer codes are valuable tools for viewing technical information and performing hardware diagnostics. Universal codes such as *#06# are useful on almost every smartphone, while manufacturer-specific codes can help technicians test displays, speakers, sensors, batteries, and network functions.
It is important to understand that there is no single "secret number" that unlocks hidden features on every phone. Support varies widely between Android brands, iPhone models, software versions, and mobile carriers. Using only trusted, documented codes helps you avoid unnecessary risks while making the most of your device's built-in diagnostic capabilities.
The most useful phone code is not the one that promises unrealistic hidden features—it is the one that provides accurate information about your device safely. Always verify compatibility with your phone model before trying any diagnostic or service code.
