Smartphones arenโt just about flashy apps and sleek interfaces โ they also come with hidden menus, diagnostics tools, and secret testing modes that you can unlock with special dialer codes.
Whether youโre using a Samsung Galaxy, an iPhone, a Xiaomi phone, or a Realme device, there are USSD and MMI codes that give you access to deep system information, hardware testing features, and carrier-specific settings.
In this guide, weโve compiled the largest, most up-to-date collection of smartphone secret codes in 2025, categorized by brand and use case.
Table of Contents
๐ What Are Secret Smartphone Codes?
Secret smartphone codes, also known as USSD (Unstructured Supplementary Service Data) or MMI (Man-Machine Interface) codes, are special combinations of symbols and numbers entered into your phone dialer. They are not visible in the standard menu and are often used by:
- Developers
- Repair technicians
- Mobile network engineers
- Advanced users
These codes can help:
- Access hidden menus
- Test hardware (speaker, display, sensor)
- View detailed phone/battery/network info
- Enable/disable advanced features
โ ๏ธ Warning: Some codes can perform factory resets or change important settings. Use them with caution.
โ Universal Smartphone Codes (Work on Most Android & iPhones)
| Code | Function |
|---|---|
*#06# | Displays IMEI number |
*#*#4636#*#* | Phone, battery, usage, and Wi-Fi info |
*#*#7780#*#* | Factory data reset (erases user data) |
*#*#8351#*#* | Enable voice call logging |
*#*#8350#*#* | Disable voice call logging |
*#*#1472365#*#* | GPS Test |
*#*#232339#*#* | Wireless LAN test |
These codes may not work on all phones due to software restrictions or regional lockouts.
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๐ Apple iPhone Secret Codes
Unlike Android, Apple doesn’t support USSD for diagnostics, but you can access some hidden functions via these codes:
| Code | Function |
|---|---|
*3001#12345#* | Field Test Mode (signal strength, cell tower info) |
*#06# | Display IMEI number |
*#67# | Call forwarding status when busy |
*#61# | Call forwarding status if unanswered |
*#21# | Check all diversion settings |
*#31# | Hide your caller ID |
๐ Note: These codes open system-level call/network settings and do not offer hardware diagnostics like Android.
๐ฑ Samsung Secret Codes (One UI 6 / Android 14)
Samsung phones offer one of the most powerful hidden menus for diagnostics:
| Code | Function |
|---|---|
*#0*# | General test mode (display, speaker, vibration, etc.) |
*#0228# | Battery status and ADC readings |
*#0011# | Service Mode (network & signal strength) |
*#1234# | Firmware version |
*#32489# | Encryption and security info |
*#12580*369# | HW & SW version |
*#0808# | USB settings (media transfer/debug mode) |
*#2663# | Touchscreen firmware |
*#9090# | Diagnostic configuration |
*#7465625# | Check SIM lock status |
Samsung โ More Hidden Diagnostic Codes
*#*#34971539#*#*โ Camera firmware & hardware info*#*#197328640#*#*โ Samsung service mode (advanced testing)*#*#232338#*#*โ View Wi-Fi MAC address*#*#232331#*#*โ Bluetooth test mode
These Samsung secret codes are mostly read-only and are useful for checking hardware details before buying a used phone.
๐ด Xiaomi / Redmi / POCO (MIUI 14/15)
| Code | Function |
|---|---|
*#*#6484#*#* | Full hardware test mode (QC Test) |
*#*#4636#*#* | Battery/Wi-Fi/Phone info |
*#*#8255#*#* | GTalk Service Monitor |
*#*#232338#*#* | Wi-Fi MAC address |
*#*#1234#*#* | MIUI Build info |
*#*#1111#*#* | FTA Software version |
*#*#2222#*#* | FTA Hardware version |
Xiaomi / Redmi / POCO โ Extra Testing Codes
*#*#64663#*#*โ Full hardware diagnostic test*#*#6484#*#*โ CIT engineering test menu*#*#4636#*#*โ Phone, battery & network information
These codes are especially helpful on MIUI and HyperOS devices for sensor and hardware verification.
๐ก Realme / Oppo (ColorOS)
| Code | Function |
|---|---|
*#*#3646633#*#* | Engineer Mode (MediaTek SoC only) |
*#808# | Hardware Test Mode |
*#888# | Hardware version & QR code |
*#6776# | Software version |
*#1234# | Firmware info |
๐ Note: Many codes may not work in newer ColorOS 14+ due to UI restrictions.
๐ข Vivo Secret Codes
| Code | Function |
|---|---|
*#558# | Hardware test menu |
*#*#4838#*#* | Testing menu |
*#*#7777#*#* | Factory reset |
*#06# | IMEI number |
๐ต OnePlus (OxygenOS 14+)
| Code | Function |
|---|---|
*#808# | Hardware diagnostics |
*#1234# | Software version |
*#801# | Engineering Mode (ADB/root only) |
*#06# | IMEI |
OnePlus โ Advanced Diagnostic Codes
*#808#โ EngineerMode (manual hardware testing)*#*#4636#*#*โ Network, battery & usage statistics*#*#759#*#*โ Factory testing menu (older OxygenOS models)
Some OnePlus codes may vary depending on OxygenOS version and region.
๐ฎ Huawei / Honor
| Code | Function |
|---|---|
*#*#2846579#*#* | Project menu (network, updates) |
*#*#1472365#*#* | GPS test |
*#*#232339#*#* | Wi-Fi test |
*#06# | IMEI |
๐ Motorola (Android One)
| Code | Function |
|---|---|
*#*#2486#*#* | CQATest hardware test |
*#*#4636#*#* | Usage and battery info |
##7764726 | Verizon menu (carrier-specific) |
๐น Nokia (Android One Series)
| Code | Function |
|---|---|
*#*#4636#*#* | Testing info |
*#06# | IMEI number |
*#*#7780#*#* | Factory reset |
Motorola / Nokia (Android One Devices)
*#*#4636#*#*โ Network and battery information*#*#2486#*#*โ Hardware diagnostic menu (supported models)
Android One devices usually support fewer brand-specific codes but still allow basic diagnostics.
How to Use Secret Codes Safely
Before using any smartphone secret code, keep these points in mind:
- Always enter codes in the Phone dialer, not in settings or browser
- Read-only codes are safe, but reset or factory codes can erase data
- Backup your data before using advanced diagnostic or reset codes
- Some codes may not work on carrier-locked or region-restricted phones
- If a menu opens automatically, do not change settings unless you know what they do
Secret codes are meant for testing and information, not for unlocking or bypassing phone security.
Practical Use Cases
You can use smartphone secret codes to:
- Check hardware condition before buying a used phone
- Diagnose battery, sensor, or network issues
- Verify IMEI and device authenticity
- Test camera, display, speaker, and vibration without apps
These codes are especially useful for technicians, resellers, and advanced users.
โ ๏ธ Warning: Use With Caution
- โ ๏ธ Some codes perform irreversible actions like resetting your device.
- ๐ต Some codes are disabled by default on carrier-locked or newer phones.
- ๐งช Use only the codes you understand โ especially those under “engineer mode” or “reset.”
๐ Frequently Asked Questions (FAQ)
Q1: Why don’t some codes work on my phone?
Some codes are disabled by manufacturers, carriers, or vary based on Android version.
Q2: Can I unlock hidden features using these codes?
Yes, but most features are read-only. Some may unlock test modes or settings.
Q3: Will using secret codes void my warranty?
No, simply entering codes usually doesn’t void warranty โ unless you change system settings or root the device.
Q4: Are these codes safe to use?
Most are safe if used to view information. Avoid reset or engineer codes unless you’re sure.