He was Junior European Champion in the 470 class three years in a row and he has competed at the Olympic Games in two different classes, first in the 470 class in Beijing 2008 and in the Laser class in London 2012. Karlo won 2nd place at the 2019 World Championships in the Melges 32 class and 2nd place at the 2015 World Championships in the J/70 class.