WiFi Free Space Loss Calculator

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I often like to do a quick FSPL calculation to understand how far a WiFi signal might travel and usually have to search around to find an FSPL calculator. So, I put my own together so save me the search next time.

To understand what a signal level might be over a particular distance, simply select the channel you are interested in, enter the EIRP of your AP and the distance involved. Then hit the 'Calc' button:

Enter Frequency (Ghz):

EIRP: (dBm) Distance: (m) Signal Level (dBm):
Loss (dB):



(Caveat: this is a theoretical signal loss in free space, once you have obstructions, all bets are off. The actual signal level received by the client will depend on the gain (or loss) of its antenna)

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