Indian shot-putter Om Prakash Karhana has qualified for the 2012 London Olympics as well as next month's World Championships. Karhana qualified after winning gold in an IAAF meet at Szombathely in Hungary on Friday. Karhana registered a personal best of 20.04 metres to cross the 20-metre qualifying mark for the London Olympics and the World Championships to be held in Daegu, South Korea from August 27. Karhana had finished third in the Asian Championships at Kobe, Japan earlier this month. Defending his shot put title, he managed a bronze with a season's best of 19.47 metres.