Viewing Cell Phone Signal Readings

Why is the actual signal reading important?  Why not just look at the bars?  The bars on a cell phone are like a gas gauge in a car.  The gas gauge does not tell you how many gallons of gas you have, it just lets you know about how much gas you have.  You can travel 20 miles and the gauge will not change, but you have less fuel in your tank.  Bars on a cell phone are similar.  Your strength of your signal will fluctuate, but your bars may not.  Bars on your cell phone don't tell you the real story.  If you display the -dBm signal reading on your cell phone you will have a more accurate, real signal reading.
The -dBm signal displayed on your cell phone will most likely fluctuate up and down a few dB.  This is normal.  Tower signal strengths do change depending upon load.  Some cell phone show this up and down fluctuation quite well because they refresh quickly, other cell phone refresh at a slower rate and may not show a difference every minute or so.

What does the -dBm signal mean?

So how do I interpret the -dBm signal reading.  Below is a guideline of how to understand the signal reading.
  • -50 to -60 (very, very strong, near a cell tower)
  • -60 to -70 (extremely good, rare)
  • -80 to -85 (normal reading, very common)
  • -90 to -95 (starting to get weak)
  • -95 to -98 (weak, dropping calls)
  • -100+ (poor unusable signal)
With the advent of smartphones, technical information is much easier to view on the phone.  Most smartphone allow the user to display the actual signal reading being received from the cell tower.  Different phone operating systems have different methods of displaying the data.  Below we show how to do this on the most popular smartphones.

Android Phones

The actual cell signal strength on an Android phone can easily be displayed using a couple of menu options.  Follow the steps below.
  1. From the HOME screen select MENU
  2. Choose SETTINGS (small gear icon).
  3. Find ABOUT PHONE and select it.  There may be some variations of where ABOUT PHONE is located by operating system version.
  4. From the ABOUT PHONE menu list select STATUS
  5. In the list under STATUS there is SIGNAL STRENGTH field with a -dBm number.


Apple iPhone (models 3x, 4x, 5s, and 5c)

The following is supported by all major carrier iPhones except T-Mobile and some unlocked models.

  1. Dial *3001#12345#* then press CALL
  2. The FIELD TEST screen will appear
  3. The bars at the top of the screen are now replaced by a -dBm number

Blackberry (older models 8700 etc.)

  1. Select OPTIONS from the main menu
  2. select STATUS from the OPTIONS menu
  3. The top line will now be the signal strength, a -dBm number
An alternative method is hold down ALT and push N M L L and your bars will be replaced with a -dBm number.  repeat this process to return to regular bars.

Windows Phones

We are not aware of any way to display field test mode information on Windows phones.  Check your app store for any available signal strength apps.

USB Modems and AirCards using Verizon Access Manager

Once connected place your mouse cursor over the bar signal indicator at the bottom of the screen.  A little window will pop up with a -dBm signal strength.

Verizon MIFI Units

See your user manual for instructions on how to go into Advanced Mode to see signal strength.