# The formula for calculating the PhoneRank from the RF Safe Score

The RF Safe Score is a measure of the potential risk from cell phone usage over a lifetime, as determined by the specific absorption rate (SAR) values of a device. However, this score is a sum of negative numbers that, with one last step, we can turn the RF Safe Score into an easy-to-visualize 5-star ranking system to compare across different devices. That’s why we developed the PhoneRank system, which converts the RF Safe Score into a simple star rating.

The formula for calculating the PhoneRank is:

PhoneRank = (100 – RF Safe Score) / (100 – 0) * (5 – 0)

This formula takes the RF Safe Score, which is a negative number and turns it into a positive number between 0 and 100. This is done by subtracting the RF Safe Score from 100. This positive number is then divided by the range of possible scores (100 – 0) to give a decimal between 0 and 1. Finally, this decimal is multiplied by the range of possible star ratings (5 – 0) to give the final PhoneRank.

For example, let’s say the RF Safe Score for a phone is -71.

Using the formula, we would get:

PhoneRank = (100 – (-71)) / (100 – 0) * (5 – 0) PhoneRank = 171 / 100 * 5 PhoneRank = 2.9

So, this phone would receive a PhoneRank of 2.9 out of 5 possible stars. It is important to note that the higher the PhoneRank, the lower the potential risk associated with using the device and vice versa.

The PhoneRank system makes it easy for consumers to compare the potential risks of different devices at a glance and to make an informed decision about which device to choose. It’s essential to remember that the PhoneRank is a simplification of the RF Safe Score and should not be used as the sole deciding factor when choosing a device. It should be considered alongside other factors such as cost, features, and durability.

In conclusion, the RF Safe Score is a useful tool for assessing the potential risks of cell phone usage. The PhoneRank system simplifies this by converting the RF Safe Score into a simple star rating, making it easy for consumers to compare the potential risks of different devices and make an informed decision. It is important to remember that the PhoneRank simplifies the RF Safe Score and should be considered alongside other factors when choosing a device.