WIFIALR is presented as a software solution capable of identify between different types of indoor human activities as: GO TO BED, FALL, PICK UP, RUN, SIT DOWN, STAND UP and WALK using Machine Learning techniques. A generated console and window interface alert is shown to user in response to human movement through a LOS (Line of Sight) of two transmission and reception WiFi devices. This solution has a great potential in medical assistance for disabled and elderly people with high risks to suffer a fall or trying to do health risk activities; about security, could be used to prevent home robbery when hosts are absent or sleeping in different rooms where incident happens; also, could be considered to avoid risks and injuries to people in certain areas in factories or offices.