Beacons allow you to set the transmit power to levels such as -30dBm, -20dBm, -16dBm, -12dBm, -08dBm, -04dBm, 0dBm and +4dBm. The number of actual setting values depends on the beacon. Our article on Choosing the Transmitted Power explains these values and how they relate to distance.
We have been asked ‘What are the Estimated Distance/s for Tx Powers?’. This depends on the beacon, the environment and the receiver. An analogy is someone shouting a word. How loud does someone have to shout to be heard a certain distance? It depends on how clear the person shouts, how much noise there is and how well the person listening can hear. With beacons it depends on the beacon (mainly antenna) design, how much radio frequency (RF) noise there is, the degree of RF reflections and the receiving ability of the device (smartphone or gateway) you are using.
The only way to determine the relationship between distance and power is experimentally and it will likely change over time as the environment changes.