If you are wondering what exactly are secret codes, well, these are USSD codes that bring about some info when you dial them from your smartphone. Android smartphones come with their own set of secret codes but every different smartphone comes with its own set of codes, derived by its manufacturer and thus, it’s a tough task keeping a track of them. On the other hand, there are a handful of cool iPhone secret codes that work universally on all iPhones. Curious about it? Don’t be! Here are 8 cool secret iPhone codes that you must know:

1. Field Test Mode

Code: *3001#12345#*

This secret code on the phone triggers the Field Test Mode, which brings you a lot of technical details around your network. That’s not all though, as you can also use this code on your iPhone to get a more granular look at your network’s signal strength. The bars are a good way to view signal strength but if you want to know the exact strength, you can use this code to view signal strength in decibels. So, here’s how to do it:

When you enter the code in your iPhone’s dialer and hit the call button, you will taken to the Field Test page, where you will find various networks details. Then, just press hold on the Power/Lock button unless you get the “Slide to turn off” option. Once you are on the power off screen, just press hold the home button and you will see the bars replaced with the network strength in decibels.

iPhone Field Test Mode

Once done, wait for 20-30 seconds for the network to settle down. Then, you can take a note of your signal strength, If the number is above -80 (-70,-60..), the signal strength is close to full and if it’s below -110 (-120,130..) , the network has pretty weak signal. It’s important to note that the signal strength will vary depending on if you are connected to a 3G or 4G network.

iPhone secret codes signal in decibels

To disable the decibels and get back the usual network bars on your iPhone, you can open Field Test page again with the secret code and tap on the top-left edge, which says “Phone” or you can simply press the home button once.

2. Hide Caller ID

Code: *31#mobile number

If you have a carrier unlocked iPhone or a carrier that supports hiding your caller ID, you can use this secret code to present your caller ID as “Unknown” or “No Caller ID”. All you need to do is use the code that works in your country and add the mobile number you want to call anonymously and press dial.

iPhone Secret Codes hide caller ID

Here is a list of the codes that work in different countries:

Albania:#31# (cell phones)
Germany:*31# or #31#
Hong Kong:133
New Zealand:197
North America:#31# or *67
Netherlands:*31* or #31#
South Africa*31*
South Africa#31#
South Korea:*23 or *23#
Switzerland Landline:*31#
Switzerland Mobile:#31#
United Kingdom:141

We tried the code to mask our caller ID but it failed to work for us, so we will suggest you to keep your expectations low.

3. Check SMS center

Code: *#5005*7672#

Every text message that you send from your phone first goes to a server or SM S center number, which then sends it to the number you send it to. If you have been facing a few issues regarding SMS, it’s best to check the SMS center number and you can use this secret code to do exactly that. You can just enter the code in the iPhone’s dialer and press “call”.

iPhone Secret Codes check SMS center

4. Call Waiting

Code: *#43# (Check Status), *43# (Enable Call Waiting), #43# (Disable Call Waiting)

As you might have guessed, this iPhone secret code simply lets you check the status of Call Waiting and enable or disable it with ease. This should come in handy if you just can’t seem to find the Call Waiting options in your iPhone.

iPhone Secret Codes Check Call Waiting

5. Call Barring

Code: *#33# (Check status), *33*pin# (Enable Call Barring), #33*pin# (Call Barring)

Call Barring lets you block all incoming or outgoing calls on your phone and if you want to check its status or enable/disable it on your iPhone, you can use this code. The “pin” here is the SIM Pin, which is the lock on your SIM card. You can enable it in iPhone Settings->Phone->SIM PIN.

iPhone Secret Codes Check Call Barring

6. Call Forwarding

Code: *#21# (Check Status), *21# (Enable or Disable Call Forwarding), *21mobilenumber# (Divert Calls to this Number)

Don’t want to be disturbed by a phone call while you watch your favorite sports team fight it out? Well, for people unaware, Call Forwarding is a feature that lets you divert incoming calls to your other number or even a voicemail and you can use these secret codes to check its status on your phone or to enable it and divert calls to another number.

iPhone Secret Codes Check Call Forwarding

7. Calling Line Presentation

Code: *#30#

If the recipient of your calls aren’t able to view your mobile number, there might be problem with your number’s Calling Line Presentation. In that case, you can use this code to check if Call Line Presentation is enabled or disabled.

iPhone Secret Codes Check Calling Line Presentation


Code: *#06#

Chances are, you already knew about this code, didn’t you? For people unaware, all phones come with their unique identification number and you can use this USSD code to check it on almost any phone. For more details on IMEI and its use, you can check out our detailed article on the same.

SEE ALSO: How to Install Georestricted Apps on iPhone

Like the Cool iPhone Secret Codes?

So, these were some of the cool secret iPhone codes that you can use. You will find a number of other codes for the iPhone across the web but we can assure you that they don’t really work as they claim to. We tried out the aforementioned codes and they work. So, try them out on your iPhone and let us know if you find them helpful. Sound off in the comments section below.


  1. I pressed #30# and it disabled my call presentation line… what do I press to enable my call presentation again?