Github: https://github.com/DoctorLai/FreeSpaceCalculator

Online Path Loss Calculator:

Source code: https://github.com/DoctorLai/FreeSpaceCalculator/blob/master/simple_calculator.html
Online Tool:
https://propagationtools.com/wireless/free-space-path-loss-calculator-with-api/

Free Space Calculator API

Source Code: https://github.com/DoctorLai/FreeSpaceCalculator/blob/master/api_freespace.php

Proof of Work

doctorlai is my github ID and you can view my profile https://github.com/DoctorLai which has my steemit URL page.

propagationtools.com is one of my domains. From the tool page you can see my github link at the beginning.