Samsung secret codes are short sequences you type into the Phone dialer to open hidden engineering, diagnostic and information screens on your Galaxy device. These are technically called USSD codes (when they query the mobile network) and MMI codes (when they trigger something on the handset itself). Most of the genuinely useful ones are standard Android MMI codes that work across nearly every Galaxy phone running One UI, from a Galaxy A-series budget model to the latest S-series flagship. They let you check your IMEI, run a quick hardware self-test, or view call-forwarding status without digging through menus.
To use any of these, open the Phone app, tap the keypad, and type the code exactly as shown. Codes that begin and end with asterisks and hash symbols usually run the moment you finish typing; some, like the IMEI check, run as soon as the last character is entered. If a code does nothing, your carrier or your specific One UI build may have disabled it, which is increasingly common on newer firmware.
The most useful Samsung secret codes
The table below lists widely documented standard Android MMI/USSD codes. Two of them are destructive. Read the Caution note before you touch those, because they cannot be undone once started.
| Code | What it does |
|---|---|
| *#06# | Displays your IMEI number (and serial on some models). Useful for warranty, insurance and unlock requests. |
| *#0*# | Opens the hardware self-test menu so you can check the screen, touch, sensors, vibration, camera and speakers. |
| *#1234# | Shows the current firmware version (AP, CP and CSC build numbers). |
| *#0011# | Opens the service mode screen with network and signal status information. |
| *#*#4636#*#* | Opens the testing menu with phone, battery and usage statistics (availability varies by build). |
| *#21# | Shows call, SMS and data forwarding status so you can see if anything is being redirected. |
| ##002# | Cancels all active call forwarding rules on your line. |
| *2767*3855# | Caution: This is a full factory reset and reformat. It wipes all data immediately with no confirmation prompt. Do not enter it unless you intend to erase the phone. |
| *#*#7780#*#* | Caution: This wipes app data and downloaded apps (a partial reset). Back up first, as deleted data cannot be recovered. |
The two destructive codes behave like a wipe from Settings, so the same warning applies: if a Samsung account or Google account is signed in, Factory Reset Protection (FRP) will lock the phone after the wipe and demand the last synced Google or Samsung credentials before setup can continue. Always remove your accounts first if you plan to sell or give the device away.
Safety first before you experiment
Hidden menus expose calibration and reset functions that are easy to trigger by accident. Before you try anything beyond the harmless information codes, make a complete copy of your phone. Our guide on how to back up and restore Android devices walks through Samsung Cloud, a Google account sync, and a local Smart Switch copy so nothing is lost.
Keep these habits in mind:
- Never type a reset code casually. If you actually want a clean wipe, use a controlled method instead, such as the steps in how to hard reset any Android mobile, and sign out of your Google and Samsung accounts first to avoid the FRP lock.
- Do not change values in the self-test or service screens. Use them to read information, not to adjust radio bands or calibration.
- If the phone is misbehaving and codes do nothing, the underlying fix may be at a lower level. See how to use recovery mode to fix your Android phone for clearing the cache or performing a recovery-based reset.
Used responsibly, Samsung secret codes are a fast way to confirm hardware health, read your IMEI, and check network settings. Treat the two wipe codes with the same respect you would a factory reset, and you will avoid the most common mistakes people make with these dialer shortcuts.
Frequently asked questions
Why do some Samsung secret codes not work on my Galaxy?
Carriers and newer One UI builds frequently disable engineering and reset codes for security reasons. The information codes like *#06# and *#0*# tend to keep working, while service-mode and reset codes are the most commonly blocked. If a code does nothing, that is expected behaviour on a locked or recent build rather than a fault with your phone.
Will a secret-code factory reset remove the Google lock?
No. A reset triggered by a code wipes your data but does not remove Factory Reset Protection. After the wipe, the phone will still ask for the Google or Samsung account that was previously signed in. Remove both accounts in Settings before resetting if you want the device to set up cleanly afterward.
Is *#0*# safe to use?
Yes. The *#0*# hardware self-test menu is read-only diagnostics: it lets you test the display, touch response, sensors, vibration, cameras and speakers without changing any settings. Just exit when finished rather than leaving individual tests running, and avoid the separate reset codes listed with a Caution note.
