I love hidden features on my devices. It’s fun to learn something new about the tech you use every day, to discover the little features that aren’t advertised. And unless you spend a lot of time messing around in the Phone app, dialer codes are likely among those hidden features for you as well.
Dialer codes are, as their name implies, codes you dial into your iPhone’s phone app. These codes can do a lot of different things: One allows you to remove your caller ID when dialling other numbers, while another can show you how strong your current cell signal really is. They can change settings, or show you data you didn’t know about.
Now, full disclosure, these codes can be finicky. Many are carrier-specific, so they might not work depending on your cellular connection. I ran into a few issues myself with some of these codes with AT&T on an iPhone 12 Pro Max. Still, these are tried and true, so they should work for the right combination of device and carrier.
Here are some of the codes we think are most interesting and useful.
Place anonymous calls on your iPhone
The mobile phone, with its caller ID, made placing anonymous calls a thing of the past. That is, unless you know how to hide your caller ID. All you need to do is add *67 in front of the phone number you’re trying to reach, and your call will appear as “NO CALLER ID” to the other line. If you find this option doesn’t work for you, #31# is also known to work.
This dialer code is perfect for one-off situations where you don’t want your call’s recipient to know your number or ID. But if you need all of your calls to be anonymous, you can actually do so from Settings > Phones > Show My Caller ID.
Show your caller ID
If you do opt to turn off Show My Caller ID, you might need to know this code. Some numbers don’t allow calls from unknown callers, so you’ll need to reveal your identity in order to get through. Other times, you might be calling someone you want knowing who you are. In any of those cases, all you have to do is add *82 to the number you’re dialling.
Block outgoing calls
Handing your iPhone over to someone to use can be an excruciating exercise in trust. If one of your worries is about who that person could call with your iPhone, know there’s a quick dialer code to block all outgoing calls. Dial *33* followed by a four-digit PIN and # (example: *33*1234#). That PIN ensures someone can’t easily disable the block. Once you hit the call button, the feature should load, then kick into effect. You can disable it by typing in the same code and PIN combination.
Check your iPhone’s cell signal strength
Have you ever experienced poor cell service, only for your iPhone to claim you have full bars? Us, too. That’s where the field test can come in handy; this hidden menu contains plenty of data about your cellular system, but the one area we’re looking for is how strong your connection is.
Note: this is one time where older iPhones have a feature newer iPhones don’t. If you have a 5G iPhone (iPhone 12 or iPhone 13 series), you can’t use this tip; all iPhones can use the field test menu, but LTE-only iPhones will be able to see their cell signal strength.
You can use the dialer code *3001#12345#* to pull up the field test menu. Make your best attempt to ignore the sea of information this menu provides, and tap the hamburger menu icon on the right. Now, scroll down to LTE, and choose Serving Cell Meas. Check the numbers next to rsrp0 and rsrp1, which represent your current cell tower and the backup tower, respectively. The closer the number is to zero, the better your connection to the tower. The further away it is, the worse the connection is.
Check your iPhone’s IMEI
Your iPhone IMEI is a unique number that can be used to identify your specific device. For this reason, it is often used to check if a phone has been reported as stolen. It’s important you don’t give away this number to anyone that asks, but how can you check for it in the first place?
One way is through a dialer code. Dial *#06#, and, before you ever have a chance to hit the call button, you’ll see a Device Info page appear. Your IMEI will be the second number listed, along with other assorted numbers depending on your specific type of iPhone.
See your carrier details
Want to know how many minutes you have left on your plan? Try *646#. If you want to check your current balance with your carrier, dial *225#. On AT&T, I can type *3282# (*DATA#) to see how much data I have left on my current month’s plan.
Enable call waiting
While you can set up call waiting from Settings > Phone > Call Waiting, you can also quickly enable it with a code. Just type *43# to enable it. This setting is likely already enabled, however; without it, incoming calls go right to voicemail if you’re currently on another call.