Signal bars are good indicators, but they don't provide the accurate signal strength on the iOS device. Hence, it's not easy to exactly figure out how strong the signal is on the iPhone. However, there is a simple “Field Test Mode” that helps you toggle the signal strength bar into numbers that show how strong the signal is.
The signal strength mainly varies based on your location. So, if you ever aren't able to call or find the audio quality too weak to handle during a call, you might want to check out the actual status of the signal.
How to Enable Field Test Mode to Change Signal Bars to Numbers on iPhone
- Open the Phone app
- Dial this number: *3001#12345#*
A new screen opens up. This is known as the “Field Test Mode.” As it happens, you'll notice that the signal bars have changed into a (negative) number. This is the actual signal strength of the network that your iPhone connects to.
If you tap the signal strength number, it changes to bars. Tap again, and you get the numbers. It's a tap-to-toggle here.
How to Check the Actual Signal Strength
The signal strength usually fluctuates between -100 and -70 but can vary vastly depending on your location and the real strength of the signals your iPhone is receiving. The closer the number is to zero, the stronger the signal is.
The unit of signal strength is dBm (also known as dBmW or decibel-milliwatts. It can show both very large and small values in a short form. Thanks to the unique ability, it's found in radio, microwave and fiber-optical networks as a more efficient measure of power.
How to Revert to Signal Bars
Just press the home button and the iPhone will snap out of Field Test Mode. The signal bars will toggle back on.
If you want to have the tap-to-toggle feature permanently enabled, you can easily achieve it by following this:
- Open the Phone app
- Dial *3001#12345#* and tap Call
- In the Field Test Mode, press the power button till the ‘slide to power off' shows
- Don't slide. Just press the home button for as long as it takes to close the slider.
- The Field Test Mode will exit, but the signal strength indicator will remain in numbers. Tap to toggle the indicator to bars and back to numbers.
So, that's the simplest way to find out the signal strength on iPhone! Make the best use of this little trick to keep confusion at bay. Have any feedback? Share it with us.