Apple Secret Codes & USSD Dial Codes (2026)
iPhone field-test & carrier codes
Apple takes a much stricter approach to hidden diagnostics than Android manufacturers, so iPhone secret codes are mostly standard GSM MMI strings rather than proprietary service menus. What survives is still genuinely useful: Field Test Mode exposes the raw cellular measurements iOS hides behind signal bars, and the call-forwarding, call-waiting and caller-ID interrogation codes report exactly how your carrier has configured the line.
Field Test Mode is the headline tool. It shows the serving cell, the frequency band in use and the RSRP value in dBm, which is the only honest way to compare reception between two locations or two SIM cards. Anything above roughly -90 dBm is strong; below -110 dBm you are on the edge of usable service.
The remaining iPhone codes are interrogation strings. They ask the network a question and print the answer, so none of them can damage the device or alter your data. There is no iPhone equivalent of the Android hardware test grid, and no dial code can jailbreak, unlock or bypass Activation Lock, whatever other sites claim.
Full Apple secret code list (16 codes)
Every code below is documented from public device and service documentation. None of these codes erase user data, but always read the risk column first.
| Code | What it does | Category | Risk level |
|---|---|---|---|
| Voicemail Forwarding Status. Shows the number and delay used for forwarding unanswered calls to voicemail. | call | Safe — read only | |
| No-Service Forwarding. Shows the number calls are forwarded to when the iPhone is unreachable. | call | Safe — read only | |
| Call Barring Status. Shows whether call barring is active on the iPhone line. | network | Safe — read only | |
| Show IMEI. Displays the iPhone's IMEI number. | info | Safe — read only | |
| SMS Center Number. Shows the message centre number used to send SMS. | info | Safe — read only | |
| Forwarding When Busy. Shows where calls go when the line is busy. | network | Safe — read only | |
| Remaining Minutes. Checks remaining plan minutes (works on some US carriers only).Community-reported · unverified | network | Safe — read only | |
| Caller ID (incoming). Shows whether incoming caller ID is enabled. | network | Safe — read only | |
| Caller ID (outgoing). Shows whether your number is presented on outgoing calls. | network | Safe — read only | |
| Prepaid Account Balance. Checks prepaid balance (carrier-dependent).Community-reported · unverified | network | Safe — read only | |
| Field Test Mode. Dial then press call to open the Field Test app showing detailed cellular signal and cell data. | diagnostics | Safe — read only | |
| Call Forwarding Status. Shows all-call forwarding settings on the iPhone. | network | Safe — read only | |
| Cancel All Forwarding. Turns off every type of call forwarding on the line. | network | Caution — changes settings | |
| Call Waiting Status. Shows whether call waiting is currently enabled. | network | Safe — read only | |
| Enable Call Waiting. Turns on call waiting so a second caller can reach you mid-call. | network | Caution — changes settings | |
| Disable Call Waiting. Turns off call waiting. | network | Caution — changes settings |
How to use Apple codes
- Open the iPhone Phone app and go to the keypad, exactly as if you were dialling a number.
- Type the code precisely as shown, including the leading
*and the trailing#. Autocorrect and paste can drop characters, so type it out. - Most sequences fire the moment the final character is entered — you usually do not press call.
- If the screen does not change, press the call button once; a few USSD strings need it.
- Back up photos, messages and app data before running anything marked destructive, then confirm you are on the right device.
- Nothing at all happening usually means the code is disabled on your firmware or blocked by your carrier — it is not a fault with your handset.
Apple secret codes — FAQ
Do all Apple phones support the same secret codes?
No. Code support depends on the model, the firmware version and in many cases the carrier that supplied the handset. Older Apple models often expose more service menus than the newest releases, because manufacturers gradually lock engineering tools behind signed diagnostic apps. If a code does nothing, it has almost certainly been removed or disabled on your build rather than typed incorrectly.
Is it safe to dial Apple secret codes?
The codes we mark as "safe" only display information or open a read-only test menu, so they cannot damage your phone. Codes marked "caution" change a setting or start a hardware routine you should understand first, and codes marked "destructive" erase user data instantly with no confirmation dialog. Always back up before running anything in the destructive category.
Why does nothing happen when I enter a code?
Three common reasons: the code is not supported on your firmware, your network operator has blocked the USSD string, or the dialer requires you to press the call button for that particular sequence. Try the code on a different SIM or in airplane mode, and confirm every character including the leading asterisk and trailing hash.
Will using these codes void my Apple warranty?
Simply reading diagnostic information does not void a warranty. However, changing radio band settings, running write operations in an engineering menu, or performing a factory format can leave your device in a state a service centre may treat as user-caused. Stick to read-only codes unless you are following official repair guidance.
Can these codes unlock a network-locked Apple phone?
No. Network unlocking requires a carrier-issued unlock code or an official unlock request through your operator. Any site promising a free universal unlock dial code is misleading you. The codes listed here only expose diagnostics, network status, firmware information and factory reset routines.
How do I find my IMEI on a Apple device?
Dial *#06# on any GSM or LTE phone, including every Apple model, and the IMEI appears immediately. You can also validate the number with our IMEI checker, which runs the Luhn checksum used by the GSMA to detect mistyped or invented IMEI numbers.