Megaranto was born on October 8, 1987, in Bojonegoro, East Java. He learned to play chess at 8 years old and, at 9, participated in his first tournament. At the age of 12, he became national champion in the U-20 category, becoming the youngest U-20 national champion in the history of Indonesian chess.
He gained international attention in 2004 when he won the Asian Junior Chess Championship in Sri Lanka, achieving the International Master title in the process. Four months later, he won the silver medal in the World Junior Chess Championship in Greece.
In 2007, he achieved the Grandmaster title during the 2nd President Gloria Macapagal Arroyo Cup in the Philippines. In the same year, he won silver at the Asian Cities Chess Team Championship in Tehran.
Among his numerous achievements, Megaranto earned the Indonesian Chess Player of the Year award, and was named the Indonesian Athlete of the Year 2007 by the country's National Sports Committee. He also won the 2008 Young Indonesian Achiever Award.
He represented Indonesia in several Chess Olympiads, the first one being in 2004.